FI64290B - FILTRERANDE ANDNINGSSKYDD - Google Patents

Description

NOTICE Δ 1 OQC \ w (11> UT, .ÄG <iN? NGSS {CR! FT 64290 C (45) ratonttl -njSr.netty 10 11 1983 - - (51) Kv.ik. ^ im.a. ”A 62 B 18/02 // A 62 B 7/10 AN O (21) P * tenttlhakerm> * - P * tentw «eknlr> g 80127k (22) HakemijpUvi - AnsöVrlrgtd» * 21.Cl.80 (23) Primary cloud— Glltlghettdag 21.0 ^ .00 (41) Tullut JulkUeksI - Blfvit offentllg 22.11 80

National Board of Patents and Registration / 44 ^ N & htivlkslpanon J * moon! .Fulkal * un pvm. -

Patent- och regirterstyretsen 'An * «kan utlagd och utl.skrKten pubticerad 29. 07.83 (32) (33) (31) Requested prefix - Begird priorltet 21.05.79 25.Ο5.79 English -England (CB) 7917612, 7918269 ( 71) Racal Safety Limited, Beresford Avenue, Wembley, Middlesex HAO 1QJ,

England-England (GB) (72) Joseph Raymond Hilton, Guildfors, Surrey, England-England (GB) (7k) Qy Kolster Ab (5 * 0 Filter respirator - Filtrerande andningsskydd

The present invention relates to improvements in respirators and in particular to filterable respirators.

Filterable respirators have been known for many years, originally in the form of simple surgical masks that to some degree protect the patient from bacteria in the exhaled air of a physician or nurse. Such masks are normally simple in construction, usually pleated or wrinkled, and are applied to the face to cover the nose and mouth with textile or rubber bands. These masks do not have a very large filtering and protection effect. In recent years, filterable respirators have been introduced in the industry, the protective effect of which has not been achieved before. This has been made possible by the emergence of new filter media on the market and improved manufacturing methods, which in many cases have been automated, resulting in high-volume production at low cost. There are generally two types of such filterable respirators, one being a molded cup 2,64290 and the other a pleated sheet material mask. In a molded cup, either the filter media is placed between two low-resistance, fiber-formed cups that form an inner and outer layer that are joined together in the open mouth of the cup, usually by welding or glue, or the filter media is molded to form a cup. One or two thin rubber bands are attached to the edge of the mouth of the cup and usually a small piece of nasal metal to be molded is provided to provide a better seal around the nose. Another type of filterable respirator is made of a flat sheet of filter media that folds twice into a flat pocket with an open mouth and multiple transverse folds with one or two headbands attached to the open large edge of the pocket. The purpose of the pleats is to increase the filtration area and thus reduce the frontal velocity through the material and, as a result, to reduce inhalation and expiratory resistance and to improve the efficiency of the filter media.

Improved, more high-performance filter media with higher efficiencies, i.e. the degree of particle separation, combined with lower weight loss, making it unnecessary to increase the filtration area by forming pleats. This means that a lighter, more convenient respirator, i.e. a mask, which in some cases has greater flexibility, can be provided. Whereas the former filter media operate mainly on the principle of capture or retention, consisting of fibers, typically cellulose fibers to which short glass fibers have been added, or glass fibers added to paper or felt materials of different efficiencies, a new generation of materials consisting of microfibers, on the other hand, mechanical efficiency. These microfibers are normally inside or between two sheets. These sheets are a scrim sheet and are very low resistance and normally have nothing to do with filtration; their sole function is to protect and hold the microfibers together. The microfibers are usually polyvinyl chloride or polycarbonate. There is also an electret-type material with a similar function on the market.

Thus, the design of a respirator to take advantage of the increased efficacy of these new substances poses new problems. Because filter media is relatively expensive, the most important factor in 3,642,290 is material savings. Fortunately, the compensating advantage is that less material is needed and therefore the goal is to use as little material as possible and gain strength and wear resistance. The simplest covers, with a little more material than the cover in the form of a flat pocket, which pocket is then opened to fit the wearer's face, suffer from a number of disadvantages, not least their tendency to slam into the wearer's face during inhalation, which can be uncomfortable. , and what makes barking difficult. Such simple respirators tend to leak around the mouth of the pocket, i.e. between the face and the large edge of the pocket. It is obvious that such a large edge leakage reduces the effectiveness of the shield.

According to the present invention, there is provided a filterable respirator made of a flexible, filterable sheet material in the form of a flat pocket having a substantially frustoconical shape and opposite sidewalls, an open magnifying glass at a larger end of the fracture cone and a closed end at a smaller fracture cone. off.

The respirator according to the invention is characterized in that the closed end of the pocket is provided with first fold lines defining a substantially quadrilateral surface consisting of two triangular surfaces having a common base and opposite ends of which are located substantially at the corners of the closed end of the pocket. is perpendicular to the line joining said angles, and the triangular surfaces are turned towards each other and are in use in a relatively oblique position relative to each other.

The fold line defining the common base is preferably stiffened in its longitudinal direction to act as a reinforcing rib. Other of the first fold lines may be stiffened in their longitudinal direction.

The flexible filterable sheet material is preferably welded, the first fold lines being formed by welds made in the material, which have a longitudinal stiffening effect on the fold lines. The flat outlet pocket can be made of a single blank, which is in the form of two frustocones with the narrower ends of the cones joining together and the cones being placed on the coverings and joined together along the side edges of the pocket, e.g. by welding.

64290

The open pocket of the pocket can be provided with an inwardly directed sealing strip, as described in pending patent application No. 7,911,595.

The present invention will be described in more detail below with reference to one embodiment with reference to the accompanying drawing, in which Fig. 1 is a plan view of a sheet of filter material and shows a way in which blanks of an filterable respirator embodiment according to the present invention can be cut therefrom; Fig. 2 is a perspective view of the cut blanks of Fig. 1 at the end of the cutting step; Fig. 3 is a plan view of a blank of an embodiment of a filterable respirator according to the invention; Figs. 4a and 4b are schematic sectional views showing welds that can be used in the manufacture of a filterable respirator; Figures 5-9 show the steps of manufacturing a respirator from the blank of Figure 3; Figures 10-12 show additional steps in the manufacture of a filterable respirator; Fig. 13 is a side view of the respirator in the open condition; Fig. 14 is a front view of the filterable respirator also in the open condition; Fig. 15 is a perspective view of the respirator of Figs. 13 and 14 in use; Fig. 16a is a schematic diagram showing the operation of the filterable respirator of Figs. 13-15; Figures 17a-17e show different manufacturing steps of the modification of the respirator of Figures 13-15; Fig. 18 is a side view of another embodiment of a filterable respirator in the open condition; Fig. 19 is a view of the respirator of Fig. 18 in an open condition as seen from its open end; Fig. 20 is a view similar to Fig. 19 but with the cover opened; Fig. 21 shows a manufacturing step of the cover of Fig. 18; and Figures 22 and 23 are substantially plan views of the filterable respirator of Figure 18 in a folded condition.

The respirator shown in Figures 13-15 is made of a flexible filterable sheet material, e.g. 5 64290 as described above, initially in the form of a flat, substantially frustoconical pocket 1 as shown in Figure 5, the narrower end 2 and both side edges 3 of which are closed and wider. head 4 is open. For the sake of clarity, the upper wall 5 of the pocket 1, which is on the user's nose during use, and the lower wall 6, which is located under the user's jaw during use, will now be described.

This flat pocket 1 is folded, as described below, to obtain a quadrilateral surface at the closed end of the pocket consisting of two substantially identical triangular surfaces 7, these triangles having a common base 8 and tips e, f against the base 8, which tips are located at the closed end of the flat pocket. 2 corners. The common base 8 is located on a line perpendicular to the line connecting the tips e, f, and the triangular surfaces 7 face each other and are used obliquely against each other.

The fold line forming the common base 8 of the triangular surfaces 7 preferably extends in each wall of the pocket along lines 9 and 10 to the open end of the pocket, i.e. to the large edge 4.

In addition to the above-mentioned fold lines, the cover preferably has fold lines 15 starting from the tips e and f and passing to points on the top wall edge 4 of the pocket located between the fold line 9 and the side edges 3. These fold lines 15 together with the fold line 9 form an inverted V-shaped groove 16 of the top wall 5 which fits the wearer's nose and thus is guaranteed to adapt the pocket top wall 5 to the wearer's face shape, thus reducing edge leakage around the nose and between the nose and cheeks.

The cover is held on the face by one or - as shown - by two strips 13, 14 attached to the edge 4. The head strips can be attached to A1, A2 and B1, B2 or both can be attached to the ends C1, C2 at the ends of the side edges 3 or to a single the tape can be attached at C1, C2.

First, the manufacture of the above respirator for a sheet material to be welded, e.g., high frequency welding, ultrasonic welding, or ball welding, will be described. The cover is made of the blank 20 shown in Figure 3, which consists of two truncated cone-shaped parts placed together by a narrower female. This preform has advantages in terms of manufacturing economy, as it can be made from a sheet of material 21 shown in Figure 1, which is considerably wider than the blank, e.g. 3 m wide with a length of about 100 m. It can be seen from Figure 1 that numerous sheets 21 can be continuously cut. blanks located in longitudinal rows with the blanks of one row being displaced longitudinally by half of the length of the blank with respect to the blanks of the adjacent row. Thus, only the side edges of the sheet 21 remain a wreck. The blank can be, for example, 21 cm wide at the wider end of each truncated cone, 3.5 cm wide at the narrow end of each truncated cone and approx. 19 cm long, so that the cone angle is approx. 59 °.

The sheet of filter material 21 is passed through a continuous high-speed cutting machine which cuts continuous longitudinal zigzag cuts 22 forming the side edges of the blanks, and possibly also makes transverse cuts 23 forming the ends of the blanks. These cross-sections 23 are not the full width of each row of blanks to ensure that the blanks of each row of blanks are held together to facilitate subsequent handling. At the end of the cutting machine, the rows of blanks are folded as shown in Fig. 2.

The next step, which can be combined with the cutting step or simply with making the cuts 23, is to print the weld pattern shown in Fig. 3 on each blank. These welds comprise barrier welds at the end edges of the blank, which prevent the material from rubbing at these edges, a longitudinal center weld 25 defining fold lines 8, 9 and 10 and four welds 26, 27 defining fold lines 11, 12.

The entire weld pattern can be printed in one operation or can be assembled from several straight welds.

The function of these welds, as shown in Figure 4a, is to compress and flatten the material in the weld area, and it has been found that this provides longitudinal stiffness to the weld line. It is possible, by using suitably shaped electrodes or in the subsequent heating step, to profile such a weld, e.g. as shown in Figure 4, in order to increase its longitudinal stiffness. This profiling can at least be carried out on the part of the weld 25 which forms the common base 8 of the triangles 7.

After this step, the blank is folded twice as shown in Fig. 5 to bring both the top and bottom walls 5, 6 and the closed end edge 2 of the pockets and thus the pocket finally formed into the formation. formed by the welded edges 24 of the open large edge 4. In the next step, shown in Fig. 6, the pocket is opened by pulling the ends n, m of the central weld 25 and at the same time pressed down from the center of the weld 25 to fold the blank along the welds 25, 26 and 27 and to form the triangles 7 shown in Fig. 7. Bringing the points n and m further apart encloses the triangles 7 together, as shown in Fig. 8. This results in triangular wings 30 which are then folded towards point n to fit evenly against the rest of the pocket, as shown in Figure 9.

This step provides fold lines 15 extending from the tips e, f to the open edge 4 of the pocket. However, these fold lines 15 may be preformed by making corresponding welds to the blank at the same time as forming welds 24-27.

The suspension cover is otherwise completely formed in Fig. 9, except that the headbands have not yet been attached to the above points.

An additional folding step can be performed as shown in Figures 10-12. The triangular surfaces 7 are separated and turned downwards in opposite directions around the fold line 8 until they are against the rest of the pocket, as shown in Fig. 11. This results in a substantially rectangular flat package that can be easily slipped into the pocket by the user, possibly inserted into the shell. The headbands can be wrapped around the package, as shown in Figure 12.

A small deformable metal strip 31 (Fig. 14) may be attached to the top wall of the respirator to extend over the tip of the groove 16 adjacent the edge 4 to improve tightness at the back of the nose.

To use the respirator, it is returned to the state shown in Fig. 9 and then opened by pulling the ends of the side edges 3 apart, resulting in a cover in the form shown in Figs. 13 and 14.

It is obvious that the shape of the respirator described above is inherently advantageous in two important respects.

The cover 5 forming the top wall of the trench 16 comprises adapt it difficult to adapt sealable areas on two sides of the nose. In addition, the strip 31 is preformed into a U-shape when the cover is folded and is thus ready to be placed on the user's nose when he puts the cover on his face. The user is not required to make a conscious operation to shape the strip, although such may be necessary to bring the strip into a comfortable nasal shape.

8 64290

Although the respirator described above is described as being made of a weldable material so that fold lines 8, 9, 10, 11 and 12 may be formed by welds, it is understood that whether the material is weldable or not, these fold lines may be formed by other means or simply from pre-made bends. Some or all of these fold lines may be reinforced, in which case the reinforcement may be performed by forming reinforcing elements, e.g. plastic ribs, on the fold lines, e.g. by injection molding, or otherwise, whereby the plastic strips may be proliferated and / or held in a folded state.

Other filter materials that could be used in the shield include, for example, an activated carbon fabric interposed between two layers of pads to form a gas and vapor filtering respirator. In said activated carbon fabric, the activated carbon is in the form of a fabric originally woven from man-made fibers, e.g. rayon. Activated carbon impregnated filter media can also be used. Alternatively, one or more layers of particulate filter media may be combined with the activated carbon fabric or activated carbon impregnated filter media to provide a thinning shield capable of filtering particulate materials in addition to gas and vapor.

The general shape of the finished cover, i.e. the mask, and thus its suitability, is dictated by the dimensions of the original blank shown in Figure 3 and the dimensions of the four-sided area consisting of triangles 7. If this four-sided area is rectangular, the resulting cover is symmetrical with respect to a center line parallel to line X in Fig. 12. By making the fold lines 11 and 12 of different lengths, the shape of the cover can be slightly changed. The four-sided area can be, for example, rhombic.

Alternatively, line II can be made longer than line 12, that is, the line connecting the tips e and f (Fig. 3) is made shorter than the line connecting the tips g and h, so that these lines do not intersect at their centers. The resulting shape can be described as an inverted kite, resulting in a respirator having a side view as shown in Figure 12, where the fold line 12 is parallel to the center line X and the fold line 9 forms an angle of about 25 ° with the center line X. This is almost a classic ori-nasal dome shape.

9,64290

In one embodiment, the connecting line of tips e and f is 8 ditches, the connecting line of tips g and h is 10 cm long, and these lines intersect at a point 4 cm from tip h and 6 cm from tip g, so the angle between welds 25 and 26 is 45 ° and the angle between the coals 25 and 27 is 33.7 °.

To facilitate manufacture, the four-sided area may be rectangular, with the two said connecting lines having a length of 9.5 cm and intersecting at their centers.

It can be seen from Fig. 16 that the finished cover, i.e. the mask, can be considered to comprise a frame consisting of fold lines 8, 9, 10, 11 and 12, between which there is a filter material. Folding lines 8, 9, 10, 11 and 12 can be compared to compression supports connected by pins at their ends. Welds running along the side edges 3 are subjected to tension during exhalation and may be compressed during inhalation, which is why compression stiffness is desirable. The support formed by the fold line 8 is very important because it gives the cover vertical rigidity. The effective pin joints at the tips e and f can thus be rounded around the support 8, which gives some flexibility and mobility to the cover, which can thus easily adapt to a flat or narrow face.

When the user's jaw moves, e.g., while he is speaking, the tips e and f move in three dimensions, thus relieving the load that would otherwise affect the back of the nose and cause the cover to fall. In addition, the protective effect of the fold of the fold lines 8-12 effectively prevents it from slipping on the wearer's face, even if it becomes clogged and thus becomes ineffective.

The respirator described above can be modified by providing it with, for example, inwardly directed sealing strips as described in the pending patent application No. 7,911,595. To this end, on the contrary, the frustoconical part 35 can be added to each end of the blank, as shown in Fig. 17a, and the end edge of each can be made more or less inwardly curved. After forming the fold lines 8-12, the blank is folded in half twice and welded along its side edges 3, as shown in Fig. 17b. The flat pocket thus formed is then turned "upside down", as shown in Fig. 17c, and said ii-socket cone portions are turned inwards, resulting in an inwardly sealing strip 36 which may extend around the entire mouth of the pocket or be shorter, e.g. 3 regions of the ends 10 64290 or in addition to the nasal region, but does not extend below the jaw, as explained in the above-mentioned unresolved patent application.

It is to be understood that the pocket is inverted between the steps shown in Figures 17b and 17c to ensure that the sealing strip provides only a smooth surface for the face.

Figures 18 and 19 show another modification of the filterable thinning guard shown in Figures 13-15.

The cover corresponds exactly as shown to the cover shown in Figures 13 and 14 (and similar parts are denoted by the same reference numerals) except that the bottom wall 5 of the cover has fold lines 40 defining a triangular area 41 divided by fold line 12. The base of this triangular region 41 runs along the open edge 4 of the pocket between the side edges 3 and the opposite tip of this base is located at or in the region of the tip g of the triangles 7.

As shown in Figs. 21 and 22, the warp angle area 41 is delimited and the fold lines 40 are formed while the wings 30 are folded together. The fold lines 40 are formed by pushing at rr. inwards and by turning the 7 adjacent parts of the wall together. This creates two triangular areas which are turned together against each other and have a common base running along the Line 12.

The immersion cover is opened in exactly the same way as the cover described above, except that when the ends of the side edges 3 are pulled apart, the triangular area 41 extends over the mouth of the plane, as shown in Fig. 20. Then all that is needed is to pull the end of the fold line 12 outwards to flatten the triangular area 41.

This area 41 is located when the cover is placed on the face, under the chin, the fold lines 40 then running mainly along the edges of the lower jaw. The lower wall 6 of the cover is thus conveniently adapted to the shape of the user's chin and the parts of the cheeks close to it.

An additional advantage of inserting the triangular portion 41 is that the cover in the folded state, as shown in Figures 22 and 23, has a substantially rectangular shape that fits comfortably in the pocket without the need for the additional folding procedures described in connection with Figures 10-12. It is noted that Figures 22 and 23 show the same cover in the folded state, but in Figure 23 the cover is oriented in parts for insertion into the chest pocket.

ix 6 4 2 9 0

The respirators described above can be further stiffened by adding weld lines or plastic strips to the triangular surfaces 7, these additional weld lines or plastic strips being parallel to or oblique to the fold line 8, e.g. parallel to the fold lines 11 and 12.

It should be noted that the term filtering material or filter material already used before or after is used to denote a material that removes one or more unwanted components from a gas or vapor; the component may be in the form of particles and / or molecules and may be removed mechanically and / or electrostatically and may be absorbed and / or adsorbed by the filter media.

Claims (8)

12. , 64290 A filterable respirator made of a flexible filterable sheet material (21) in the form of a flat pocket (1) having a substantially frustoconical shape and opposite side walls (5, G), open size (4) in a larger area of the fracture cone and a closed end (2) at the smaller end of the frustoconical, characterized in that the closed end (2) of the pocket (1) is provided with first fold lines (8,11,12) defining a substantially quadrilateral surface consisting of two triangular surfaces (7) , having a common base (8) and having tips (e, f) opposite this base located substantially at the corners of the closed end (2) of the pocket (1), the common base (8) being perpendicular to the line connecting said angles, and triangular the surfaces (7) face each other and are in use in a relatively oblique position relative to each other. Respiratory protection according to Claim 1, characterized in that the fold line defining the common base (8) is stiffened in the longitudinal direction. A respirator according to claim 1, characterized in that the first fold lines (8, 11, 12) defining said four-sided surface are stiffened in the longitudinal direction. A respirator according to claim 2 or 3, wherein the sheet material is weldable, characterized in that one or each of the fold lines (8, 11, 12) stiffened in its longitudinal direction is formed by a weld in the sheet material. Respiratory protection according to Claim 2 or 3, characterized in that one or each of the longitudinally stiffened fold lines (8, 11, 12) is defined by a stiffening element attached to the sheet material. Respiratory protection according to Claim 5, characterized in that the stiffening element is made of a plastic material. Respiratory protection according to one of the preceding claims, characterized in that the substantially four-sided surface is square. Respiratory protection according to one of Claims 1 to 6, characterized in that the substantially four-sided surface is an oblique handrail.