JP2003530907A - Respiratory nose filter - Google Patents

Abstract

The present invention relates to a means for protecting the human respiratory system from dusty particles, especially allergen-carrying particles. INDUSTRIAL APPLICATION This invention can be used as a nasal filter, an artificial respirator, etc. This device has one or more inflow passages serving as intake air passages and a hollow main body having one outflow opening, and the shape of the inner surface of the main body is a shape close to a truncated cone, and The channel is formed in a conical large base, each inflow channel has a combined axial direction of a tangential component and an axial component, the outlet opening is formed in a conical apex (small bottom), and The surface is coated with an adhesive substance that can hold dust and allergen particles.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD OF THE INVENTION

The present invention relates to the field of human respiratory protection, which effectively removes dust-like particles (particularly allergen-carrying particles) from inhaled air without adding significant resistance to inspiratory and expiratory movements. To be able to clean. The present invention is
It can be used as a nasal filter or in a ventilator or the like.

[0002]

[Prior art]

A known respiratory filter (International Publication WO 86/04249) is in the form of two nasal capsules and includes a filter member impregnated with a deodorant or a drug. The capsule is inserted into the nostril. The intake air passes through the filter member to clean the air.

Another known breathing filter (“intranasal filter”, US Pat. No. 5,117,820) is formed into an oblong cylinder made of synthetic spongy material. After being radially compressed, the filter becomes a cylindrical shape with a diameter that allows it to be placed in the nasal cavity of the human body. In the nasal cavity of the human body, this filter material expands to fill the nasal cavity. Air purification in this filter is achieved by the intake air passing through a filter member made of synthetic spongy material, where particles are trapped.

Yet another breathing filter (“nasal filter” (US Pat. No. 3747597))
Is known and has a plurality of filters that are inserted into the nasal cavity (nostrils). The internal cavity of each filter has a shape close to a truncated cone. A spherical filter member is arranged in the inner cavity of the filter. This filter works like a conical valve. That is, in the process of the expiratory movement, the spherical filter member arranged inside the filter cavity moves to the bottom of the large cone, and at this position, the passage of the expiratory air is not obstructed. On the other hand, in the process of inspiratory action, the filter member moves to the bottom of the small cone and “closes” the opening in the bottom so that the intake air passes only through the spherical filter member.

Yet another known breathing filter (British Application No. 2216806) is constructed in the form of a device with an insert (inserted into the nostril) and has an inner flange for holding the filter member in place. It has a hollow tubular body with. The inserts, when combined, form a clamp to secure the filter to the septum of the nose. In the process of the suction operation, the air is cleaned by passing the air through the filter member including the hollow main body having the insert inside.

[0006]

[Problems to be Solved by the Invention]

Air purification in each of the filters described above is accomplished by passing air through a filter member made of various materials, leaving air pollutants and allergens on the member during the course of intake operation. The filter member is the main constituent element of each of the filters described above. However, the use of the filter member impedes breathing. This is because the filter member impedes the free access of the air flow and provides a considerable resistance to the air flow being drawn in.

Most similar (in technical nature) to the present invention is the respiratory filter "nasal and oral filter" (US Pat. No. 5,787,884), which is characterized by an air passage free of filter material. . This filter is designed to protect the respiratory airways against dust and allergens contained in the intake air.
The filter is shaped so that it can be placed in the oral cavity or nasal cavity of the human body (in the latter case, due to the elasticity of its body, it comes into close contact with the inner surface of the nasal cavity). Air passages are provided in the filter for easy human breathing. This passage has a curved shape and has a special dust particle trap zone located in the vicinity of the position where the air passage changes direction. Due to the curved shape of the air passage, the intake air changes its direction of movement several times. The dust particles contained in the intake air enter the trapping zones and are retained here because these zones are covered with a sticky substance.

In this design, as compared with the case of the design with the filter insert,
The movement of the airflow is less disturbed. However, the air passage in the filter is narrow and tortuous to increase the probability of trapping dust particles, which creates a significant resistance to the airflow passing through the filter (although this resistance is Much lower than the resistance that occurs when using a filter). In addition, the resistance to the movement of the air flow increases as the clogging progresses during the operation of the filter.

[0009]

[Means for Solving the Problems]

The problem to be solved by using the present invention is a respiratory filter that can be used as a respiratory protection device (protects the respiratory organs of the human body from dust particles, particularly allergen-carrying particles), and has a low aerodynamic resistance. A feature is to provide a breathing filter that is invisible to others (in use).

The essence of the invention is a breathing filter having a body with one or more inflow passages for the passage of intake air and one outflow opening, according to the invention the body is formed hollow. , The shape of the inner surface of the main body is a shape close to a truncated cone, the inflow passage is formed in the bottom of the large cone, and each inflow passage has an axial direction in which an axial component and a tangential component are combined. The outlet opening is formed in the apex (small bottom) of the cone, and the inner surface of the main body is covered with an adhesive substance capable of holding dust and allergen particles contained in the intake air.

The purification of the intake air in the device is carried out in the "swirl chamber" of the filter formed by the body, whose shape is close to the shape of a truncated cone. As air enters this cone, it spirals in a spiral due to the shape of the inflow path in the region of the base of the great cone. The inflow passage is formed so that the axial direction thereof is a combination of two components, that is, an axial component and a tangential component. When the dust particles enter the spiral flow, they move to the body wall by the action of the centrifugal force, hit the body wall and stay on the sticky substance that covers the whole body from the inside.

For convenience in using the device as a nasal filter, the body has a longitudinally curved and / or oval cross section, in other words a shape close to that of the nasal cavity. May be.

The body of the filter may be made of an elastic material to comfortably house the filter in the nasal cavity. Siloxane elastomers widely used in medical articles (eg, siloxane gums) can be selected as such materials [Chemical Encyclopedia
-Moscow: Sovetskaya Encyclopedia Publishing-House, 1990, vol. 2, p.
510].

The body may also be formed from a porous hydrophilic material (eg polyurethane foam). Because of the absorption of excess water present in the nasal cavity, such substances further enhance the convenience of using the filter.

In order to securely house the filter in the nasal cavity and to further seal the gap between the filter body and the inner surface of the nasal cavity, the outer surface of the body is made of a special elastic or ductile material. Has a different sealing collar. This material is also porous and hydrophilic,
It is also possible to absorb excess water generated in the nasal cavity. Siloxane rubber can be used as the elastic material, and silicon-acrylic latex can be used as the ductile material [Chemical Encyclopedia-Moscow: Sovetskaya Encyclop
edia Publishing House, 1990, vol. 2, p.510].

Furthermore, the outside of the large cone bottom may have a convex shape, and the inflow passage may be configured to partially pass through the side surface portion of the main body. Such an arrangement results in a wider air intake area and a smoother airflow entering the filter (in other words, without a sudden change in velocity vector). After all, such an air intake structure can reduce the resistance to breathing by 10 to 15%.

In order to reduce the number of particles not captured by the adhesive layer on the inner surface of the body,
A special collar is formed around the outflow opening and this collar is oriented inside the body. This collar, together with the apex (small bottom) of the cone and the inner wall of the body, forms the inner ring-shaped chamber. Particles that did not adhere to the body wall are trapped within this chamber.

The inner ring-shaped chamber can also be coated with the above-mentioned adhesive substance in order to further improve the retention of dust particles.

For the same purpose, the surface of the air inlet as well as the outer surface of the large bottom of the conical body may be coated with said adhesive substance.

As the adhesive substance applied to the inner surface of the main body, the surface of the ring-shaped chamber, and the air inflow path, for example, an electrostatic coating agent can be used [Electrets / Under the edito
rship of G. Sessler translated from English-Moscow. 1983]. Such a coating agent can be produced based on a polymer, salt, or copolymer (copolymer) having a hydrophilic bond or a hydrophobic bond. Glycerin can be used as a base for a sticky substance composition because it is characterized by stickiness, does not dry and works well in moistening dust.

The filter body is made of a material having a permanent electrostatic charge, for example, electret electret [El
ecrets / Under the editor ship of G. Sessler Translated from English Mosco
w, 1983]. In this case, the electrostatic charge of the body promotes the polarization of the dust particles, making them easier to adsorb to the filter body.

On the inner surface of the body (somewhere in the middle of the length of the filter), one or more protrusions are provided for the purpose of separating fine particles, most of which remain in the axial airflow due to their small weight. Has been. The protrusions are oriented transverse to the spiral line along the axial direction of the air inlet channel on the inner surface of the body. These projections have, in cross section, the convex shape of an aerodynamic wing. The geometrical dimensions of this protrusion are selected based on the following relationship.

[0023]     0.1R <h <0.3R     0.25H <L <0.8H   here,     h is the projection height in the radial direction,     R is the maximum radial dimension of the internal space of the main body,     L is the amount of protrusion of the protrusion on the body axis,     H indicates the length of the internal space of the main body.

When an air flow flows around the protrusion, a low pressure region is generated immediately above the protrusion (for example, L.
See G. Loytsyanskiy, Fluid and Gas Mechanics-Moscow, Nauka, 1970, p211). Due to this region, the air flow moves with the fine particles from the axis to the body wall, where the fine particles are trapped in the adhesive layer.

The projections also delay the circular movement of the air flow in the area of the outflow opening of the filter without generating further turbulence. By virtue of the vortex delay, a reduction in the filter's aerodynamic resistance (and thus in resistance to breathing) can be achieved.

The above geometrical relationship of the protrusion parameters was obtained experimentally. When the projection height (h) in the radial direction is larger than 0.3R, the turbulent flow of the air flow sharply increases in the entire space of the filter, adversely affecting the purification of the intake air. When h is smaller than 0.1 R, the above-described effect of reducing the aerodynamic resistance of the filter is not seen. L> 0.8
For H (ie, the protrusion extends along almost the entire body),
The projection divides a certain area, and the air is stagnated and dust is accumulated there. This continues until this very dusty air is exhausted, which is trapped in the main airstream and carried to the filter outlet opening. Further, when L> 0.8H, the protrusion starts to interfere with the normal vortex of the air flow. When the value of L is less than 0.25H, the above-mentioned effect of reducing the aerodynamic resistance of the filter is not seen.

[0027]   In the manufacturing method, the protrusion may be formed by residual deformation of the body.

For convenience in use as a nasal filter, the device may consist of two bodies joined by a flexible bridge. In this case, better wearing of the filter and mutual orientation of the body within the nasal cavity is achieved. The bridge can be formed as a permeable film with an adhesive layer for better contact and less prominence on the outer surface of the nose.

[0029]   The essence of the invention is illustrated in the accompanying drawings.

[0030]

DETAILED DESCRIPTION OF THE INVENTION

The filter (FIGS. 1 and 2) has a frustoconical body 1. Air inflow path 3
The (intake air passage) is formed in the large conical bottom 2 of the main body 1 (this large conical bottom has a convex shape from the outside). Each inflow path 3 has an axial direction in a direction in which a tangential component and an axial component are combined, and allows intake air to pass through in an appropriate direction. The apex (small bottom) of the cone 4 of the body 1 has an outflow opening 5 around which a collar 6 is formed, which, together with the inner surface of the body 1, forms an inner ring-shaped chamber 7. A sealing ring 8 is provided on the outer surface of the body 1 (close to the large conical bottom 2), and a protrusion 9 is formed on the inner surface of the body 1. In cross section, the protrusion has the shape of the convex portion of the aerodynamic wing. The geometric size of the protrusions 9 is selected on the basis of the above relationships.

The main body 1, the inflow passage 3 and the inner surface of the inner ring-shaped chamber 7 are coated with an adhesive layer, in particular polyisobutylene.

FIG. 3 shows a state in which the filter of the present invention is placed in the nasal cavity 10. The sealing ring 8 serves as packing and fixing means for the filter.

FIG. 4 shows two bodies 1 of the nasal filter connected by a flexible bridge 11.

During the intake process, the air containing dust particles is sucked into the filter through the inflow passage 3 formed in the large cone bottom 2 of the main body 1 and enters the internal space of the main body 1. In this process, the intake air swirls and travels in a spiral trajectory inside the body 1 due to the shape of the illustrated channel 3. Under the action of the centrifugal force generated when the air moves in this manner, the dust particles move to the peripheral portion of the air flow, collide with the wall of the main body 1, and are captured by the adhesive layer covering the wall. The deposition of dust particles on the adhesive layer is performed over the entire length of the main body 1. Dust particles not trapped on the adhesive wall of the body 1 enter the inner ring-shaped chamber 7, which is also coated with an adhesive layer.

Due to the turbulence of the air flow within the axial region of the body 1, some of the small dust may be carried by the air flow to the nasal cavity through the opening 5. This phenomenon is prevented by one or a plurality of protrusions 9 formed and arranged on the inner surface of the main body 1 so as to cross the direction of the air flow. When the airflow collides with the protrusion 9, a low-pressure region is generated above the protrusion 9, and this low-pressure region draws a turbulent airflow to the peripheral portion together with small dust. In parallel with this, the projections 9 delay the rotational movement of the air flow in the region of the apex (small bottom) of the cone 4 without generating further turbulence. Due to the vortex-delay effect, a reduction of the filter's aerodynamic resistance of about 1.5 times (and thus reduced resistance to breathing) can be achieved.

The filters were tested on a specially designed test bed. Wheat flour (fineness 10/10
μm) and outdoor dust (powderiness 3 ÷ 15 μm) mixed with pollen (powderiness 15 ÷ 25 μm) and cocoa powder (powderiness 5/20 μm) were used for the purpose of simulating dust. The dust was put in a container and was ejected from there into the separator by an air flow. The separator separated the air-dust mixture into two equivalent air streams.
The airflow equivalence (that is, the equivalence of deposition per unit time) is measured by the flowmeter (Manoraz
Ltd., Israel flow meters were used in the testing process). Then, one of the air streams was directed to the first paper filter and the second air stream was directed to the second paper filter through the nasal filter under test. The movement of both air streams was performed by suction with an exhaust fan.

[0037]   The dust capture efficiency (E) was determined by two methods.

1) Weigh the dust adhering to the first and second filters. In this case, the dust trapping efficiency was determined by the following equation: E = 100 (1-W ₁ / W ₂ ) (%) where W ₁ and W ₂ are dusts attached to the first and second filters, respectively. Is the weight of.

2) Visually count the number of particles attached to the first and second filters (these particles were observed using a digital camera connected to a microscope and computer). In this case, the dust trapping efficiency was determined by the following equation.

E = 100 (I−N ₁ / N ₂ ) (%) Here, N ₁ and N ₂ are the numbers of dusts attached to the first and second filters, respectively.

Using both of the methods described above, particles of 10 μm or larger in size can be removed from the air by the nasal filter under test with an efficiency of 88 ÷ 100% (ie air of this size can be purified). ). The accuracy of the measurement was 1%.

The increase in resistance due to the filter in the nose was measured as the difference in pressure drop between the full-scale model of the nose with and without the filter. As a result of this measurement, it was found that the resistance of the filter does not exceed 5 mm (50 Pa) of water at a flow rate of 15 liters per minute for two nostrils. This corresponds to hygiene requirements and respiratory equipment standards.

[0043]   The type of nasal filter under test has a frustoconical shape with the following dimensions.

[0044]     Large base of cone Oval with dimensions of 9 x 10 mm     Cone top (small bottom) oval with dimensions of 6 x 9 mm     Height 13 mm   The filter body had two spiral projections of the following dimensions.

Protrusion length of protrusion on filter shaft (L) 4 mm Protrusion width 3 mm Protrusion height (radial direction) (h) 1 mm With the above geometrical dimensions, the filter is suitable for air cleaning parameters and air flow. It was possible to capture up to 4 mg of dust without degrading the resistance. When the average dust content in the air is in the range of 1/2 mg / m ³ , one filter can be effectively used for 8 hours or more. At the same time, the frequency of filter replacement is determined primarily for hygiene reasons and convenience of use, rather than the filter capacity for trapped dust, since filters made from thermosoftening plastic, for example by injection casting, are less expensive. To be done.

As described above, this filter has a human respiratory tract of 10 ÷ 50 which is included in the air.
It is an effective and efficient device for protecting against dust (eg from pollen) with sizes in the μm range.

The filter is convenient to use and meets aesthetic requirements. This filter does not cause any inconvenience to the person using it. This is because there is no filter insert in the air passage. The fact that the filter has a soft elastic or ductile sealing layer, or that the entire filter can be made of an elastic material, ensures a hermetic seal and is free of irritation in the nasal cavity. The size and color of the filter makes it virtually invisible to others.

[Brief description of drawings]

[Figure 1]   It is a figure which shows the external appearance of the filter of this invention.

[Fig. 2]   It is sectional drawing of the filter of this invention.

[Figure 3]   It is a figure which shows the example of installation of the filter in a nasal cavity.

FIG. 4 shows two filters connected to each other by a flexible bridge.

─────────────────────────────────────────────────── ─── Continued front page    (81) Designated countries EP (AT, BE, CH, CY, DE, DK, ES, FI, FR, GB, GR, IE, I T, LU, MC, NL, PT, SE, TR), OA (BF , BJ, CF, CG, CI, CM, GA, GN, GW, ML, MR, NE, SN, TD, TG), AP (GH, G M, KE, LS, MW, MZ, SD, SL, SZ, TZ , UG, ZW), EA (AM, AZ, BY, KG, KZ, MD, RU, TJ, TM), AE, AL, AM, AT, AU, AZ, BA, BB, BG, BR, BY, CA, C H, CN, CR, CU, CZ, DE, DK, DM, EE , ES, FI, GB, GD, GE, GH, GM, HR, HU, ID, IL, IN, IS, JP, KE, KG, K P, KR, KZ, LC, LK, LR, LS, LT, LU , LV, MA, MD, MG, MK, MN, MW, MX, NO, NZ, PL, PT, RO, RU, SD, SE, S G, SI, SK, SL, TJ, TM, TR, TT, TZ , UA, UG, US, UZ, VN, YU, ZA, ZW (72) Inventor Gersiman, Michael             Israel, 42823 Zoran, 78 Ira             Noto Street (72) Inventor Litvin, Simon             Massachusetts, United States             02465, Newton, 31 Gilberts             Treat F-term (reference) 2E185 AA08 BA04 BA11 CA03 CB07                       CB15 CB16

Claims (17)

[Claims] 1. A breathing filter having a hollow body having one or more inflow passages serving as intake air passages and one outflow opening, wherein the inner surface of the body has a shape close to a truncated cone. The inflow passage is formed in the large bottom of the cone, each inflow passage has an axial direction in which the axial component and the tangential component are combined, and the outflow opening is in the apex (small bottom) of the cone. A breathing filter whose inner surface is coated with an adhesive substance that can hold dust and allergen particles contained in inhaled air. 2. The respiratory filter of claim 1, wherein the body has a longitudinally curved shape and / or an elliptical cross-section that approximates the shape of a nostril. 3. The breathing filter of claim 1, wherein the body is made of an elastic material. 4. The respiratory filter according to claim 3, wherein the main body is formed of a porous hydrophilic material. 5. The respiratory filter of claim 1, wherein the outer surface of the body has a sealing ring formed of an elastic or ductile material. 6. The respiratory filter according to claim 5, wherein the sealing ring is made of a porous hydrophilic material. 7. The respiratory filter according to claim 1, wherein a large bottom of the cone has a convex shape on the outside of the main body. 8. The respiratory filter according to claim 1, wherein the inflow passage is configured to partially pass through a side surface portion of the main body. 9. The respiratory filter according to claim 1, wherein an electrostatic coating agent is used as the adhesive substance. 10. A special collar directed inwardly of the filter body is formed around the outflow opening, the collar forming an inner ring-shaped chamber with the apex (small bottom) of the cone and the inner wall of the body. The breathing filter according to claim 1, wherein: 11. The respiratory filter according to claim 10, wherein the inner ring-shaped chamber is coated with the adhesive substance. 12. The respiratory filter according to claim 11, wherein an electrostatic coating agent is used as the adhesive substance. 13. The breathing filter according to claim 1, wherein the surface of the air inlet and / or the outer surface of the large bottom of the conical body is coated with the adhesive substance. 14. The respiratory filter according to claim 13, wherein an electrostatic coating agent is used as the adhesive substance. 15. The respiratory filter according to claim 1, wherein the filter is formed of a material having a permanent electrostatic charge (eg, electret). 16. One or more protrusions are provided on an inner surface of the filter body (somewhere in the middle of the filter length), and the protrusions are provided in an axial direction of an air inflow path on the inner surface of the body. Oriented transverse to a spiral line along the projection, the projection having the shape of a convex portion of an aerodynamic wing in cross section, the geometric size of the projection being selected based on the following relationship: 0. 1R <H <0.3R 0.25H <L <0.8H where H is the projection height in the radial direction, R is the maximum radial dimension of the internal space of the main body, and L is the projection of the projection on the main body axis. The breathing filter according to claim 1, wherein the quantity H indicates the length of the internal space of the main body. 17. The respiratory filter according to claim 16, wherein the protrusion is formed by residual deformation of the filter body.