JPH0759240B2 - Earplug - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Use The present invention relates generally to earplugs and has a plurality of flanges made from an elastic polymeric material that is particularly effective in protecting the ear from noise. Regarding earplug structure.

(B) Prior Art In the United States, one of the well-known general-purpose earplugs considered by the present invention is known as "V-51R" (trade name). Details of the structure of the stoppers are described in detail by D. Tybrakstok and Etti E. Huon-Girke, April 1956, Aeromedical Rabalatori, Light Air Development Center, Air Research and Development Command, US Air Force, WADC Technical Report 56-142.
"Development of minimum and maximum dimensions for V-51R earplugs"
In a report entitled. These earplugs can be used by military personnel who are exposed to violent sounds such as shooting sounds and explosions during World War II or those who are in extremely noisy work environments such as airports and aircraft maintenance plants. Developed to protect the ears. The V-51R earplug is made of a resilient elastomeric material such as neoprene rubber and is constructed with one rearward tilting flange member extending from the nose end of a tube-shaped rubber shaft member. The flange member extends rearward from the tip of the tube-shaped rubber shaft member and is separated from the shaft member to form an annular free space therebetween. In use, this earplug is pushed into the ear canal, whereby the rearwardly extending flange member is at least partially crushed towards its inner free space, and the flange member follows the ear canal wall to provide an acoustic sealing relationship. To get.

U.S. Pat. No. 2,427,664 granted to JW Dunbar and JSS Night on September 23, 1947
And US Pat. No. 2,717,596 issued to JAS Night on September 13, 1955, include earplugs similar to the V-51R earplugs described in the above-mentioned Bracktstock report. It is disclosed. 2 and 3 of U.S. Pat. No. 2,427,664, four disc-shaped flanges extending in a direction substantially transverse to the support shaft member are arranged in order of increasing diameter. An earplug having a member is disclosed. As can be seen most clearly in FIG. 3, all four flange members in this configuration are described for insertion into the ear canal and are pushed somewhat rearwardly by the ear canal wall.

Unfortunately, the earplugs of the type described above and variations thereof known to the Applicant have several drawbacks. First of all, when properly installed, a significant proportion of wearers often experience discomfort with the use of such earplugs. This discomfort is generally perceived as a sensation of overpressure on the ear canal wall, which is so strong that it causes pain. Against such discomfort, the wearer commonly pulls the protective earplugs out of the ear canal to a position where the overpressure disappears, but this often breaks the acoustic seal between the earplug and the ear canal wall. Or weakened, which eliminates or at least diminishes the earplug's ability to protect the ear from the intended noise. This is a particularly fatal defect. This is because the wearer may actually appear to be well protected from noise by the appearance, but he or she may not be protected at all. Secondly, of course, including the dimensional differences in both ear holes in individual wearers and the dimensional changes in individual ear holes,
Due to the well-known anatomical anatomical differences in size and shape of the human ear canal, it is generally required that flanged earplugs be manufactured in a range of sizes, and effectively protect the ear from noise. Careful fitting by a trained person to assure is generally required. For example,
The aforementioned V-51R earplugs are made in five different graduated sizes, which allow 80-85% of the adult men who wear them to fit properly, according to the report by Brackstock, et al. ing. Obviously, the requirement to manufacture multi-dimensional earplugs increases its cost and complicates production. However, according to the invention,
There is provided a multi-flange earplug that can be manufactured in one size and yet comfortable to fit, and effectively protects the ear from noise for the majority of people.

(C) Object of the Invention The basic object of the present invention is to provide a new multi-flange earplug.

Another object of the present invention is to provide a new multi-flange earplug at once that is satisfactory for proper wear and yet forms the intended acoustic seal of the ear canal.

Yet another object of the present invention is to provide a novel multi-flange earplug structure that can be produced in one size and comfortably fits up to 98% of all adult users.

Still another object of the present invention is to provide a novel earplug with a plurality of flanges that can easily operate the flange member so as to expose a normally hidden portion of the earplug for the purpose of cleaning the earplug. Is to provide.

Other objects and advantages of the invention will be in part apparent and in part pointed out hereinafter.

(D) SUMMARY OF THE INVENTION In accordance with the present invention, there is provided a multi-flange earplug made of an elastic soft polymeric material, the earplug having at least three hollow rearwardly-oriented and spaced apart. A first flange member extending from a nose end of the shaft member, the shaft member having a surface supporting an array of spaced apart flange members having a substantially circular cross section. Each of the flange members in this arrangement comprises a skirt made of a soft elastic polymeric material having a relatively thin uniform wall thickness and a Shore A durometer hardness of between about 10 and about 90. The flange members in the array are successively increased in diameter starting from the nose end of the shaft member. The diameter of the shaft member inside each flange member forms an annular free space of sufficient size between the inner surface of the skirt included in the flange member and the shaft member, and the earplug is inserted into the ear hole. By doing so, the portion of the skirt is crushed into the space so that the space can be occupied.

(E) Description of the Preferred Embodiment Referring to the accompanying drawings, an earplug of the present invention is generally a shaft member 1 and at least three rearwardly-oriented and spaced flange members 10. , 20 and 30
And each flange member has a generally circular cross section. It is preferable that each of the arranged flange members extends in a convex curve from the position where the flange member is attached to the shaft member, and it is particularly preferable that the flange members have a substantially hemispherical shape. "Approximately hemispherical shape" is the chordal cross section of a hollow sphere whose outer surfaces are at substantially all positions at substantially equal distances from one geometric center, not less than 45% and not more than 55%. It means that the thing and the flange member are defined. The earplugs of the present invention can be manufactured by any suitable polymer molding technique, such as injection molding.
The basis for achieving the advantages of the present invention is the flange member 1
In selecting the elastic polymeric material used to make at least skirts 12, 22 and 32 of 0, 20 and 30.
This material is a Shore A durometer hardness (ASTM2240-81
Value of between about 10 and about 90), preferably between about 30 and about 60). Of course, the shaft member 1 can be constructed of the same type of elastic polymeric material as was used for the skirts 12, 22 and 32 of the flange member, although the Shore A durometer hardness is somewhat higher, up to about 100. It can be composed of an elastic polymeric material. In one preferred embodiment of the present invention, the material of which the shaft member 1 is made has a Shore A durometer hardness of between about 50 and about 70. However, in other embodiments of the invention, it is preferred to use one polymeric material for the overall construction for ease of manufacture.

As will be appreciated, there are many known elastic polymeric materials that can be effectively used to make the earplugs of the present invention. For example, natural rubber, neoprene rubber, ethylene butadiene (SBR) rubber, silicone rubber, EPDM rubber, polybutadiene rubber, polyurethane elastomers, ethylene vinyl acetate elastomers, acrylic vinyl acetate based elastomers, and vinyl halide polymers. All are generally suitable materials of construction, which can be generally produced in chemical plants as having the required Shore A durometer hardness, or which are suitably mixed to have the required Shore A durometer hardness. Can be done (eg in the factory or outside). A particularly preferred polymeric material is a thermoplastic silicone rubber composite, such as the thermoplastic injection moldable elastomer sold under the concept of Clearwater, Florida, USA, C-FLEX® by Polymer Technology Corporation. Types can be mentioned as an example. These silicone rubber composites are available in a considerable range of Shore A durometer hardness and can be thermoformed into fine shapes by any of the conventional thermoplastic molding techniques.
The product produced thereby can be sterilized and cleaned without deterioration. Another preferred material from which the earplugs of the present invention are made is a heat produced by the Synthetic Rubber Division, Shell Chemical Company, New York City, NY, and sold under the brand name Craton. It is a plastic ethylene butadiene (SBR) block copolymer.

The first flange member 10 extends outwardly and rearwardly from the nose end 3 of the shaft-like member 1 to form a uniform thin skirt 12 which extends along its length along its inner axis. It is spaced from the part of the strip 1. The second flange member 20 extends outward and rearward from a first intermediate point located along the length of the shaft-like member 1 to form a uniform thin skirt 22, which is Along the lengthwise direction, it is spaced from the portion of the shaft-shaped member 1 inside thereof. Similarly, the third flange member 30 extends outwardly and rearward from a second intermediate point located along the longitudinal direction of the shaft-shaped member 1 to form a uniform thin skirt 32. Is spaced along its length from the portion of the shaft-shaped member 1 inside thereof. As can be seen in the drawings, the root portions 16, 26 and 36 of the flange member skirts 12, 22 and 32, respectively, in other words, the point at which the inner surface of the skirt is joined to the shaft-shaped member 1, lies between them. It is shaped to form the smallest radius to allow for good molding, at which point the structural material is of optimum thickness and provides significant reinforcement. The design feature of this structure is that it not only gives the skirts 12, 22 and 32 maximum flexibility at the root, but also gives the skirts 12, 22 and 32 the desired "over-center" inversion. This allows each skirt to be easily flipped by hand from their normal rearward-facing orientation to a forward-facing orientation. In this manner, when inverted to the forward orientation, the inner surface of the skirt and the portion of the axial member 1 normally located inside the skirt are exposed and thereby normally hidden to the user. Easily visually inspect the earplugs,
And (or) make it available for cleaning.

The diameters of the hollow flange members 10, 20 and 30 are sequentially increased, and in a preferred embodiment of the present invention, the flange member in which one straight line L is arranged in the completed earplug is used. It is also noted that the flange members are spaced along the length of the shaft 1 so that it can be pulled in at least point contact with all. In this preferred embodiment, the diameter and spacing are such that the straight line L and the center line extending forward of the shaft-like member 1
The half-angle θ formed with C _L is chosen to be in the range between 10 ° and 16 °, with a preferred angular range of this half-angle θ being between about 12 ° and about 14 °. By sticking to such dimensional standards, it is ensured that the earplugs so constructed are usable and effective for the vast majority of users. For example, half angle θ is 13 °,
The flange member has a roughly hemispherical shape, and the first flange member 10
It has been found that the earplugs of the present invention can form an acoustically effective seal for 98% of all adult users, including females, given a radius of about 4.19 mm (0.165 inches). There is.

It will be apparent to those skilled in the art that many of the functional advantages of the present invention will be at least partially in mind. This is because the flange member in this configuration has the extent necessary to insert the earplug into the ear canal in use or under the relatively small and essentially linear force created by the repulsion against the ear canal wall. This is because it has a deformable function. In this way, a tradeoff between the hardness of the elastic polymer used, the structural material, provides a complex interaction between the special geometry and dimensions of the flange member in the earplug structure. Therefore, the structural material used for each of the skirts 12, 22 and 32 is about 10 and about 10 Shore A durometer hardness.
Not only is it important to have a value between 90, but the wall thickness of each of the skirts 12, 22 and 32 is about 0.20 mm (0.00
It is also important to be within the range of 8 inches) and about 1.27 mm (0.050 inches). In this respect, no strict and definite structural rule can be set, but generally speaking, the softer the structural material, the thicker the skirts 12, 22 and 32. The advantage of the present invention is that the skirts 12, 22 and 32 each have a wall thickness of 0.76 mm (0.030 inch) when a construction material having a preferred value of between about 30 and about 60 Shore A durometer is used. And 0.30m
It has been found that very significant advantages are obtained when in the m (0.012 inch) range. Obviously, the appropriate balance of the wall thickness of each of the skirts 12, 22 and 32, and the Shore A durometer hardness of the elastic polymer of which it is constructed, can be readily determined empirically.
In the preferred embodiment of the present invention, it is advantageous to use a resilient polymeric structural material having a nominal wall thickness of about 0.50 mm (0.020 inches) and a Shore A durometer hardness of about 40 for each skirt 12, 22 and 32. It has been found to provide a very good overall combination of earplug structure with respect to excellent acoustical seal and user satisfaction.

As already noted, the diameter of the portion of the axial member located inside each of the respective skirts 12, 22 and 32 of the flange members 10, 20 and 30 is such that the inside of the skirt has an annular free space 11, 21 and 31 is selected to allow the skirt to deform into this free space upon insertion of the earplug into the ear canal. The particular dimensions of this annular free space 11, 21 and 31 are not particularly critical and are, of course, provided appropriately to perform the functions described above. However, each annular free space 11, 21 and 31 subtracts the diameter of the inner shaft from the inner diameter at the open end of the skirt, which is the meat of the particular skirt 12, 22 and 32 located further outside. It is generally desirable to have a diameter divided by two that is at least twice the thickness. By "annular free space" it is meant that there is nothing inside the annular spaces 11, 21 and 31 that prevents or restrains the mating skirt from moving into it.

Keeping the foregoing in mind, it is within the scope of the present invention to form one constant diameter shaft member 1. However, if this is done, the obvious consideration regarding the annular free space inside each flange skirt is that the skirt of the selected uniform diameter of the shaft-like member 1 is the smallest, in other words the freedom of the skirt 12 of the nose flange member 10. It is aimed at basing on spatial considerations. Thus, if the shaft member of this considered diameter is not a relatively stiff, strong elastic polymeric material, such as having a Shore A durometer hardness of greater than about 50, then the earplug structure made will have a shaft. Is somewhat flexible along the profile 1, and the shaft is such that the second and third flanges 20 and 30 can be easily inserted into the ear canal just by inserting them. I can't support enough. Therefore, for these reasons, the diameter of the shaft-shaped member 1 is particularly
When made of a structural material having a durometer hardness of less than 50, it is made to increase, i.e., gradually increase, from the flange member to the flange member rearward, thereby gradually increasing the portion of the shaft-like member supporting the flange member. It is preferable to strengthen.

In order for the earplug of the present invention to be easily inserted into and removed from the ear canal, the shaft member 1 extends a suitable length beyond the edge 34 of the rearmost flange member 30. Preferably, its rearmost portion forms an operating portion 42 which can be easily grasped by the thumb and forefinger of the user.

It is often desirable to connect a pair of earplugs to each other with a soft cord. The earplug structure thus connected serves to prevent the earplug structure from being dropped or lost inadvertently. This is, for example, when earplugs are used in the food processing industry, or when the dropped earplugs are unclean or unusable.
It becomes important. To provide such a tethered earplug structure, the free end 40 of the shaft 1 is axially dimensioned to receive the end of the length of a soft cord (not shown) therein. Oriented grooves or openings 41 can be formed. The cord may be formed by any suitable means, such as by solvent or heat welding, or by the use of a suitable adhesive, or a cord with a diameter slightly larger at the end than the receiving groove or opening 41. The surrounding elastic polymeric material can be fixed in the groove or opening 41 in such a way that it elastically grips and fixes this cord end. For a more detailed description of the tethered earplug structure, U.S. Pat. No. D-241, issued to Patterson et al.
Reference should be made to documents such as 881, U.S. Pat. No. 4,193,396 to Wacker, U.S. Pat. No. 4,219,018 to Draper Zunia, U.S. Pat. No. D-245,202 to Asker.

In addition, the earplugs according to the invention can be used as individual ear-inserted products, as already indicated,
They can be used as plug members to protect the ears from noise, including generally U-shaped spring-loaded headbands, where the plug members are mounted inwardly at the free ends of the headbands. A more detailed description of this type of ear protection from noise can be found in U.S. Pat. No. 4,461,290 to Gardner Giunia et al. Or British Patent 1,355,052 to Metal Box Company.
You can refer to the literature such as the issue.

An earplug having a plurality of three flanges, which substantially conforms to what is illustrated here, using the structural principles described above and for purposes of illustration and not limitation, is shown. It was made by injection molding a thermoplastic silicone rubber (C-FLEX® elastomer) having a Shore A durometer hardness of about 40. With reference to the drawings, the dimensions of each part of the earplug thus made are as follows.

Overall length of shaft member 1 30.05mm (1.183in) 5.15mm (1.203in) at end 40 Diameter of shaft member 1 Inside of skirt 32 5.15mm (1.203in) Diameter of shaft member 1 Inside skirt 22 4.78mm (0.188in) Diameter of shaft member 1 Inside of skirt 12. 3.40mm (0.134in) Diameter of shaft member 1 Hemispherical flange member 4.19mm (0.165in) 10 radius Hemispherical flange member 5.15mm (0.203) radius of 20 hemispherical flange member 6.48mm (0.255in) radius of 30 hemispherical flange member 4.42mm (0.174in) 10 axial length hemispherical flange member 5.23mm (0.206in) 20 axial direction Length Hemispherical flange member 6.65mm (0.262in) 30 axial length Skirts 12, 22, 0.48mm (0.019in) 32 wall thickness Nose 3 to nose 9.78mm (0.385in) 24 Length nose Length from 3 to nose 16.48mm (0.649in) 34 Annular space 11 2.16mm (0.085in) Annular space 21 2.28mm (0.090in) Annular space 31 3.43 mm (0.135 in) half-angle θ 13 ° These earplugs were tested by 10 testers according to the test procedure of ANSI S3.19-1974. In the first test series (hereinafter referred to as the "maximum satisfaction test"), these testers were instructed to insert the earplugs into the ear canal to the maximum satisfactory position. In the second test series (hereinafter referred to as the "maximum damping test"), the tester individually pushed the earplugs by trained personnel into the ear canal to a position that established a maximum acoustic seal. . The maximum satisfaction test
An NRR value of 22 was shown, and a maximum attenuation test showed an NRR value of 25. During the maximum satisfaction test, the examiner was asked to rate the relative satisfaction of earplugs according to the following scale.

The average satisfaction score given by the tester to the earplugs according to the invention was about 3.

For comparison purposes, a similar series of tests was performed by the same testers using the prior art commercially available multi-flange earplugs. The maximum satisfaction test showed only 16 NRR values. The maximum attenuation test showed an NRR value of about 23. The average satisfaction level given to these commercial earplugs by the tester during the maximum satisfaction test was about 4.

Another maximum satisfaction test was conducted by the same testers using yet another commercially available multi-flange earplugs of the prior art. The NRR value was about 13, and the average satisfaction with these earplugs was about 6.

Since many embodiments, modifications and variations of the invention can be made in view of the above teachings without departing from the spirit of the invention, the description of the claims other than as specifically stated in the preceding paragraph It should be understood that the present invention can be implemented within the scope included in.

[Brief description of drawings]

The drawings are schematic, longitudinal cross-sectional views of earplugs according to the invention, including the various preferred embodiments of the invention. 1 ... Shaft member 3 ... Nose end 10, 20, 30 ... Flange member 11, 21, 31 ... Annular free space 12, 22, 32 ... Skirt 40 ... Free end 41 ... Groove or opening

Claims (17)

[Claims] 1. An elongate shaft member made of an elastic polymer material and also having a nose end, and at least three integrally fixed at a distance along at least a portion of the shaft member. A flange member having a substantially circular cross-section, arranged in such a manner that the diameters gradually increase, and a flange member having the smallest diameter is arranged at the nose end, which is hollow and faces rearward. And a row of flanges comprising the extending flange member, each of the flange members having a substantially hemispherical shape, each of the flange members having a diameter of about 0.20 mm (0.008 inches).
And a substantially uniform wall thickness of between about 1.27 mm (0.50 inch) and a Shore A durometer hardness of about 10
And a thin skirt made of an elastic polymeric material having a value between about 90 and a diameter of a respective portion of the shaft-like member inwardly of each skirt is such that the inner surface of the skirt and the shaft are Earplugs that are designed to form a free space in an annular manner between the earplugs. 2. A straight line that draws at least a point contact with each of the flange members in the flange row can be drawn, and the straight line intersects a center line extending forward of the shaft-like member to form a relatively small half angle. The earplug according to claim 1, wherein the gap and the diameter of the flange member are defined so as to do so. 3. An earplug according to claim 2 wherein said half angle is between about 10 ° and about 16 °. 4. The earplug of claim 2 wherein the half angle is between about 12 ° and about 14 °. 5. The earplug according to claim 1, wherein the Shore A durometer hardness of the material forming each of the flange members in the flange row is a value between about 30 and about 60. 6. The earplug of claim 5 wherein the skirt of each of the flange members has a wall thickness of between about 0.76 mm (0.030 inch) and about 0.30 mm (0.012 inch). 7. The earplug of claim 1 wherein the material forming each of the skirts has a Shore A durometer hardness of about 40 and a wall thickness of about 0.50 mm (0.020 inch). 8. The earplug according to claim 1, wherein the diameter of each portion of the shaft-shaped member inside each skirt is increased from the flange toward the rear. 9. The earplug according to claim 8, wherein the elastic polymer material forming the shaft member has a Shore A durometer hardness of less than about 50. 10. The elastic polymeric material forming the shaft member has a Shore A durometer hardness of about 50 and about.
An earplug according to claim 1 having a value between 70. 11. The earplug according to claim 1, wherein the dimension across each annular free space is at least twice the wall thickness of the skirt that regulates the space. 12. A shaft member extending rearwardly from the last flange member of sufficient length to form an operating means for handling earplugs. Earplugs. 13. The axial end of said shaft member is provided with an axially oriented groove sized to receive the end of the length of the soft cord which acts as a cord to connect it. 13. The earplug according to item 12 above. 14. The skirt of each of the flange members in the flange row is connected to the shaft-like member inside the skirt at a minimum radius, thereby minimizing the thickness of the constituent material at the connection part and at the same time, the skirt. The earplug according to claim 1, wherein the front portion is formed so as to be capable of being turned upside down by hand so that the skirt and the portion of the shaft-like member inside thereof can be exposed. 15. The earplug according to claim 1, which is made of thermoplastic silicone rubber. 16. The rear end (14,24,34) of each skirt (12,22,32) of each flange member (10,20,30).
Is at least flush with the nose end of the subsequent flange member, the flange member (10,2
An earplug according to claim 1, characterized in that the (0,30) are spaced along the axial member (1). 17. The rear end (14,24,34) of each skirt (12,22,32) of each flange member (10,20,30).
Claims, wherein substantially hemispherical flange members (10, 20, 30) are spaced along the axial member (1) so that they slightly overlap the nose end of the subsequent flange member. The earplug according to item 1.