The present disclosure relates to a filter for fluid filtration, and more particularly, to a filter for a respirator.

Background

A respirator typically includes a mask main body and one or more filter cartridges attached to the mask main body. The mask main body may be worn over the nose and the mouth on the face of a person, and in some cases, the mask main body may include a portion covering the head, the neck, or other body parts. A wearer may inhale cleaned air that has passed through a filter disposed at the filter cartridge. In a negative pressure respiratory protection device, air is drawn through a filter cartridge by a negative pressure that is generated by a wearer during inhalation. Air from an external environment passes through a filter medium and flows into an interior space of a mask main body through which a wearer may inhale the air.

Various techniques have been employed in a filter cartridge for use in a respirator. A conventional filter cartridge generally includes a filter member having an air purification function inside a frame which is made of a paperboard, a nonwoven fabric, or a plastic.

However, when the frame is formed of a rigid paperboard, a nonwoven fabric, or a resin, an adhesive power between the filter cartridge and an outer wall of a space in which the filter cartridge is mounted is insufficient, and thus an air leak is caused such that there is a problem in that the air purification function cannot be sufficiently exhibited. Furthermore, there is also a problem in that installation of a filter cartridge is difficult due to friction between the filter cartridge and the rigid frame while the filter is mounted on the rigid frame.

Summary

Therefore, an object of the present disclosure is to provide a filter for a respirator which employs a flexible frame having elasticity to be capable of being easily deformed, being easily attached to and detached from the flexible frame, and minimizing interference during installation at the flexible frame.

Also, another object of the present disclosure is to provide a filter for a respirator which is capable of maintaining filter performance even when a flexible frame is deformed.

Further, still another object of the present disclosure is to provide a filter for a respirator which employs a corrugated filter member to increase an effective area of the filter for a respirator and be capable of improving filter performance and to have an improved lifetime. To resolve the above-described problems, there is provided a filter for a respirator according to the present disclosure, which includes a corrugated filter member having a plurality of corrugated tips and at which a first valley pattern is formed between each of the plurality of corrugated tips; a flexible frame coupled to an edge of the corrugated filter member and including a connector and first and second supporters which protrude from the connector, wherein the first supporter includes a bending supporter and a plurality of protrusions protruding from the bending supporter and respectively coupled to the corrugated tips, and both distal ends of the corrugated filter member are coupled to the second supporter.

A second valley pattern may be formed between each of the plurality of protrusions, and a depth of the first valley pattern may be greater than that of the second valley pattern.

A height of the second supporter may be equal to a sum of heights of the bending supporter of the first supporter and each of the protrusions of the first supporter.

A ratio of the height of the bending supporter to a height of each of the protrusions may be in a range of 1 : 1 to 1 :2.

The flexible frame may include a thermal plastic elastomer (TPE).

A Shore A hardness of the flexible frame may be in a range of 35 to 45.

The filter for a respirator may have a radius of curvature of 40 millimeters (mm) or more.

In accordance with the filter for a respirator according to the present disclosure, filter performance thereof can be improved, a lifetime thereof can be improved, a shape thereof can be easily deformed, attachment, and detachment thereof can be easily performed, and interference can be minimized during installation at the flexible frame. Also, the filter performance can be maintained even through the filter for a respirator is deformed.

Brief Description of the Drawings

FIG. 1 is a perspective view of a filter for a respirator according to the present disclosure.

FIG. 2 is a one side view of a flexible frame according to the present disclosure.

FIG. 3 is a cross-sectional view of a filter having a curvature according to the present disclosure.

FIG. 4 is a cross-sectional view taken along line Ι-Γ of FIG. 1. Detailed Description

In the following detailed description, reference is made to the accompanying drawings which form a part of the application and in which some specific embodiments are shown as examples. However, it should be understood that other embodiments may be realized without departing from the scope or spirit of the present disclosure. Therefore, detailed content for implementing the present disclosure described below is not to be taken in a limiting sense.

All scientific and technical terms used herein have the same meaning as commonly used in the art unless otherwise noted. Definitions provided herein are intended to facilitate understanding of certain terms frequently used in the present description, and are not intended to limit the scope of the present disclosure.

Unless otherwise noted, all numbers indicating sizes, quantities, and physical characteristics of features which are used in the present description and the appended claims are to be construed as being qualified by the term "about" in all cases. Accordingly, unless indicated otherwise, numerical parameters set forth in the present specification and the appended claims are approximations that may be varied according to desired properties which are to be obtained by those skilled in the art using the teachings herein.

As used in the present disclosure and the appended claims, the singular form ("a," "an," and "the") includes an embodiment having a plurality of referents unless the context clearly dictates otherwise. As used in the present disclosure and the appended claims, the term "or" is generally used to include "and/or" in its meaning unless the context clearly dictates otherwise.

As used in the present disclosure, spatially related terms including "lower," "upper," "under," "below," "above," and "on," but not limited thereto, are used to describe a spatial relationship of an element(s) with respect to another element for convenience of description. These spatially related terms include different alignments of a device in use or in operation in addition to particular alignments shown in the drawings and described herein. For example, when an object shown in the drawings is reversed or inverted, a portion previously described as being below or under another element will be on the other element.

In the present disclosure, when a positional relationship is described, for example, when a positional relationship between two parts is described using the terms "on," "above," "below," and "adjacent," one or more other parts may be located between the two parts unless the expression "immediately" or "directly" is used.

In the present disclosure, when "having," "including," "being provided with," and the like are used, they are used as if they have open meanings, and other matters can be added in addition to those described unless the expression "only" is used. The term "respirator" refers to a device that is worn by a person and filters air before the air enters into the person's respiratory system.

The term "mask main body" refers to a structure that, at least, aligns with the nose and the mouth of a person and helps to define an interior air space separated from an exterior air space.

The term "filter cartridge" refers to a device that can be attached to a respiratory organ of a person for the purpose of filtering air before the air enters into the interior air space between the mask main body and the face of the person.

The term "integral type" refers to a thing that is made at the same time, or in which one or more among integral type components cannot be separated therefrom without damage.

The term "outside air" refers to air that contains other materials, such as contaminants, which can be harmful to a person.

The term "filtered air" refers to air from which contaminants were removed when outside air passed through a filter.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. Features of the embodiments of the present disclosure can be partially or entirely coupled or combined with each other and can be technically variously interlocked and driven.

FIG. 1 is a perspective view of a filter for a respirator according to the present disclosure. FIG. 2 is a one side view of a flexible frame according to the present disclosure.

FIG. 3 is a cross-sectional view of a filter having a curvature according to the present disclosure. FIG. 4 is a cross-sectional view taken along line Ι-Γ of FIG. 1.

Referring to FIGS. 1 to 4, a filter 10 for a respirator includes a corrugated filter member 100 and a flexible frame 200.

The corrugated filter member 100 has a plurality of corrugated tips 110, and a first valley pattern 120 is formed between each of the plurality of corrugated tips 110. Outside air flows toward an upper surface of the corrugated filter member 100 to pass therethrough, and filtered air may be discharged through a lower surface of the corrugated filter member 100.

The corrugated filter member 100 has an effective area of the filter 10 for a respirator, which is greater than that of a planar filter member, so that filter performance may be improved and a lifetime thereof may be increased. Also, the outside air flowing into the corrugated filter member 100 moves along the first valley pattern 120 to pass through the corrugated filter member 100. Accordingly, the outside air may be uniformly distributed, filtered materials such as contaminants may be uniformly slowly accumulated on the upper surface of the corrugated filter member 100, and a lifetime of the filter 10 for a respirator may be increased while maintaining performance of the filter 10 for a respirator.

A distance between adjacent corrugated tips 110 may be varied according to a size and application of the filter 10 for a respirator, and the distance may be determined on the basis of a relational expression between a thickness of the corrugated filter member 100, a height of the corrugated tip 110, the distance between adjacent corrugated tips 110, and a filter performance constant. For example, the distance between adjacent corrugated tips 110 in the filter 10 for a respirator may be in a range of 3 millimeters (mm) to 6 mm, and preferably, in a range of 4.1 mm to 4.3 mm.

Any material for the corrugated filter member 100 may be used without limitations as long as the material allows air to pass while blocking specific materials. As a non-limiting example, the corrugated filter member 100 includes a nonwoven fabric, a fabric, a paper, and the like, but the present disclosure is not limited thereto. Further, there is no limitation to a method for forming a corrugation at the corrugated filter member 100. For example, the corrugation may be formed by folding or forming a grain on a flat-shaped filter element.

A surface-treated material may be employed to enhance an air purification effect of the corrugated filter member 100. There is no limitation on a surface treatment method, and the surface treatment method may be varied according to an application thereof. In the cases of a filter that is employed in a place where particulate matter or dust particles are large and in the case of a filter that is employed when a large amount of air should be quickly drawn in, a material and a surface treatment method of a filter member suitable for each of the cases may be different. For example, in the case of a nonwoven fabric, an electrostatic treatment may be performed thereon, and a surface of the nonwoven fabric may be treated with activated charcoal.

The flexible frame 200 is coupled to an edge of the corrugated filter member 100. Also, the flexible frame 200 and the corrugated filter member 100 may be integrally formed. That is, an adhesive for a separate sealing may be omitted between the flexible frame 200 and the corrugated filter member 100, and thus a problem due to sealing using an adhesive may be prevented.

Further, only the upper surface of the corrugated filter member 100 may be exposed to outside air, and filtered air may be discharged through only the lower surface of the corrugated filter member 100. That is, there is no inflow of outside air to a side surface of the corrugated filter member 100, and thus performance of the filter 10 for a respirator may be maintained.

The flexible frame 200 may be formed of a frame material having flexibility and elasticity. A Shore A hardness of the flexible frame 200 may be in a range of about 35 to about 45. As the flexible frame 200 according to the present disclosure is superior in elasticity when compared to a conventional filter frame formed of a rigid paper, a nonwoven fabric, or a resin, which is employed as a conventional filter frame, so that the filter 10 for a respirator is easily attached to and detached from a desired place, and a sealing property between the filter 10 for a respirator and an installation region thereof is outstanding. Further, the flexible frame 200 may be formed at the edge of the corrugated filter member 100 without a separate adhesion process.

For example, the flexible frame 200 includes a thermal plastic elastomer (TPE). The TPE is a polymer material which may be molded in the same way as a plastic that becomes flexible at a high temperature, and the TPE exhibits a property of a rubber elastomer at a room temperature.

Various methods employed in a typical thermoplastic processing may be directly applied to the TPE, and leftover TPE which is produced during processing may be reused such that the TPE is economical and does not require the use of a plasticizer. In addition, the TPE has a specific gravity that is less than that of a thermosetting rubber, quality control of the TPE is easy, processing equipment having high productivity may be applied to the TPE in injection molding (hollow molding), and the like, and thus various products may be produced by partially varying a rigid portion and a soft portion of the flexible frame 200 such that a design thereof may be easy. That is, the thermal plastic elastomer is a polymer material which may exhibit rubber elasticity under a use condition and may be molded as a thermoplastic plastic under a molding condition.

However, the present disclosure is not limited by the above description, and the flexible frame 200 may be formed of a material that may be in a fluid state including a liquid, a syrup, a wax, or a melt at a specific temperature. For example, the filter 10 for a respirator including the flexible frame 200 may be manufactured by hardening or solidifying a material that may be in the fluid state at a specific temperature.

For example, a method for manufacturing the filter 10 for a respirator may include bending a filter member to cut the filter member to a desired size; inserting the bent filter member into a mold by fitting the bent filter member to a shape of the mold; heating a frame material to a temperature over a softening point or a melting point thereof and melting the frame material to be in the fluid state; and applying and solidifying the frame material in the fluid state to an edge of the bent filter member. Accordingly, the filter 10 for a respirator including the flexible frame 200 integrally formed with the corrugated filter member 100 may be

manufactured. At this point, the fluid state refers to a state including any of a liquid state, a syrup state, or a wax state. In addition, the solidifying may be performed by cooling, and, for example, the frame material in the fluid state may be cooled and solidified at room temperature or below.

More particularly, the method for manufacturing the filter 10 for a respirator may include placing a bent filter member on a primary mold having a groove-shaped installation portion at which a filter member may be installed; disposing a secondary mold on the filter member to expose only an edge of the filter member while the filter member is fixed;

additionally disposing a third mold at which an opening having an area greater than that of the filter member is formed to allow the filter member to be positioned in the opening by using the third mold; injecting a frame material in a fluid state into an edge of the filter member that is not covered by the secondary mold; and solidifying the frame material in the fluid state.

Conventionally, a sealing process using a hot gun or the like is required between the filter member and the frame and fixation of the filter member is difficult in such a sealing process, and particularly, there is a problem in that it is difficult to constantly maintain a distance between corrugations in the case of the corrugated filter member.

However, the sealing process using a separate adhesive for coupling the filter member to the frame may be omitted when manufacturing the filter 10 for a respirator including the flexible frame 200 integrally formed with the corrugated filter member 100 which is manufactured according to the above method, and thus a process is simplified and a problem, such as a sealing failure when an adhesive is used, may be prevented.

The flexible frame 200 includes a connector 210 and a supporter protruding from the connector 210. Such a supporter includes a first supporter 220 and a second supporter 230. The connector 210, the first supporter 220, and the second supporter 230 may be integrally formed.

The first supporter 220 and the second supporter 230 may define a sidewall of the flexible frame 200. The connector 210 connects to lower distal ends of the first supporter 220 and the second supporter 230 and may be formed in a closed shape having an opening that exposes the lower surface of the corrugated filter member 100. At this point, the connector 210 may include a laterally protruding flange for mounting or the like.

The first supporter 220 includes a bending supporter 221 and a plurality of protrusions 222. The plurality of protrusions 222 protrude from the bending supporter 221 and are respectively coupled to the corrugated tips 110 of the corrugated filter member 100. That is, a single protrusion 222 corresponds to a single corrugated tip 110.

As the protrusion 222 of the flexible frame 200 and the corrugated tip 110 of the corrugated filter member 100 move together, a distance between adjacent corrugated tips 1 10 may be constantly maintained. Accordingly, air may be uniformly distributed over an entire surface of the corrugated filter member 100 and filter performance may be evenly maintained.

A second valley pattern 223 is formed between each of the plurality of protrusions 222. The flexible frame 200 having such a second valley pattern 223 is easily deformed, and specifically, is easily bent and deformed with a certain curvature. Furthermore, the deformation is easier when the flexible frame 200 is bent to have a radius of curvature toward a lower side of the corrugated filter member 100 through which the filtered air is discharged.

When the flexible frame 200 is bent to have the radius of curvature toward the lower side of the corrugated filter member 100 through which the filtered air is discharged,

interference may be minimized when the flexible frame 200 is mounted on a respirator or when the filter 10 for a respirator is mounted on the respirator and then mounted on a welding shield or the like. Furthermore, when the flexible frame 200 is mounted on a respirator, a welding shield, or the like, damage due to interference may be prevented.

Also, a depth of the first valley pattern 120 formed between each of the plurality of corrugated tips 110 is greater than that of the second valley pattern 223. Accordingly, a tip portion of the first valley pattern 120 is engaged with the bending supporter 221 of the first supporter 220.

The bending supporter 221 has a single straight structure. The bending supporter 221 prevents excessive bending of the flexible frame 200 and may maintain a constant radius of curvature that allows the distance between adjacent corrugated tips 110 to be constantly maintained.

Excessive bending of the flexible frame 200 unevenly widens the distance between the corrugated tips 110 on an air inflow surface of the corrugated filter member 100 and narrows the distance between the corrugated tips 110 of the first valley pattern 120 on an air discharge surface of the corrugated filter member 100. This may increase a pressure drop and may shorten a useful life of the filter 10 for a respirator.

However, a pressure drop may almost be mitigated in the filter 10 for a respirator according to the present disclosure even when the curvature thereof is increased (even though the radius of curvature is reduced). Preferably, such a filter 10 for a respirator may have a radius of curvature of about 40 mm or more.

Referring to FIG. 3, a distance d between adjacent corrugated tips 110 may be constant, and a distance d' between the corrugated tips 110 of adjacent first valley patterns 120 may be constant. When the distance d between the adjacent corrugated tips 110 and the distance d' between tips of the adjacent first valley patterns 120 are constant, uniform filter performance may be exhibited over an entire area of the filter 10 for a respirator and a useful life thereof may be improved.

Therefore, the filter 10 for a respirator according to the present disclosure may maintain the distance between the corrugated tips 110 on the air inflow surface of the corrugated filter member 100 and between the tips of the first valley pattern 120 on the air discharge surface of the corrugated filter member 100 at regular intervals, and may maintain constant pressure drop performance up to a desired curvature.

When a ratio of a height of the protrusion 222 to that of the bending supporter 221 is increased, it is advantageous for deformation of the flexible frame 200, but excessive bending may occur. Conversely, when the ratio of the height of the bending supporter 221 to that of the protrusion 222 is increased, it may be difficult to deform the flexible frame 200 and the corrugated filter member 100. Accordingly, the ratio of the height of the bending supporter 221 to the height of the protrusion 222 is preferably in a range of about 1 : 1 to about 1 :2.

The second supporter 230 is coupled to both distal ends 101 of the corrugated filter member 100. Preferably, the distal end 101 of the corrugated filter member 100 may extend to the upper surface side of the corrugated filter member 100, and the edge of the corrugated filter member 100 may be coupled to the second supporter 230.

A height of the second supporter 230 may be equal to the sum of the heights of the bending supporter 221 and the protrusion 222 of the first supporter 220. That is, the height of the second supporter 230 and the height of the first supporter 220 may be the same as each other. Accordingly, there is an effect in which the second supporter 230 may prevent an undesired leak of outside air or filtered air, and the corrugated filter member 100 expands to increase an effective area of the filter 10 for a respirator.

Hereinafter, the present disclosure will be described in more detail by way of examples. The following examples are intended to further illustrate the present disclosure, and the scope of the present disclosure is not limited by the following examples.

Examples

Experimental Example - Curvature Radius of Filter for a Respirator

A pressure drop was measured by varying a radius of curvature the filter for a respirator with the same size in a plane. The results are shown in Table 1 below.

The larger the pressure drop, the lower the filter performance. Referring to the following Table 1, although an increase in the pressure drop was not large at a radius of curvature of about 40 mm or more, the pressure drop was significantly increased at a radius of less than about 40 mm. Therefore, the filter for a respirator according to the present disclosure preferably has a radius of curvature of about 40 mm or more.

Table 1

While the present disclosure has been described with reference to embodiments thereof, the embodiments are merely illustrative and those skilled in the art should understand that various modifications and equivalent embodiments can be derived therefrom. Accordingly, the scope of protection of the present disclosure should be construed to cover not only the following claims but also their equivalents.