Repeated or prolonged exposure to sounds of a sufficiently high sound pressure level (SPL) can cause temporary or permanent hearing loss. Earplugs and/or earmuffs are available instruments that can help reduce the sound pressure level entering a wearer's ear, thereby limiting and/or reducing the likelihood of hearing loss in the wearer. Earplugs and earmuffs, however, can have shortcomings that make them less than ideal for use in certain situations. For example, earplugs and/or earmuffs can provide uneven or inconsistent attenuation across frequencies, such that a user can be inhibited or prevented from hearing certain types sounds or noises that they may otherwise wish to hear.
U.S. Pat. No. 5,113,967, issued to Killion et al. (hereinafter, “the '967 patent,” which is hereby incorporated by reference in its entirety) describes a relatively inexpensive, high-fidelity ready-to-wear earplug called the ER20 HiFi Earplug (hereinafter, “the ER20 earplug”). The ER20 earplug uses damping combined with the length resonance of the sound channel to provide hearing protection from exposure to sounds that are intense enough to risk hearing damage or discomfort. When combined with an eartip (e.g., the E-A-R triple-flange eartip), the ER20 earplug provides real-ear attenuation within about 3 dB of the desired 20 dB attenuation target for audio frequencies ranging from 250 to 6000 Hz. The ER20 earplug has been adopted by musicians and workers that desire to protect their ears by attenuating sound without inhibiting their ability to appreciate the various qualities of the music or other sounds. In order to achieve the desired attenuation and sound quality, the ER20 earplug incorporates a “re-entry horn” design that results in a longer earplug length. That is, the re-entry horn of the ER20 earplug can be of a length that extends beyond the edge of a wearer's ear. However, an earplug that extends out of the ear can be difficult to hide, and therefore may be aesthetically or cosmetically displeasing. Moreover, a long earplug can be uncomfortable for certain users, for example, users that may be wearing a hat, helmet, or earmuffs that cover the wearer's ears.
The present technology provides an earplug, for example, a compact, high fidelity earplug. In certain aspects, the earplug includes a central column extending from an inner column tip to an outer column face. The central column can have a hollow sound channel and a column opening. In some embodiments, the earplug also has an inner platform extending radially from the central column. The inner platform can comprise one or more inner platform openings. The earplug can also include an outer platform extending radially from the central column. The outer platform can have one or more one outer platform openings. The earplug can also include a cap having an outer end. The inner platform and the outer platform define a first chamber, and the outer platform and the exterior end of the cap define a second chamber. In some embodiments, the inner platform opening(s) is configured to allow external sound to enter into the first chamber, and each outer platform opening is configured to allow sound from the first chamber to enter into the second chamber, and the column opening is configured to allow sound from the second chamber to enter into the sound channel. In some embodiments, the sound channel is configured to allow sound to flow through the sound channel towards the inner column tip.
Certain aspects of the present disclosure provide an earplug for insertion into an ear of a wearer. In some embodiments, the earplug has an inner end and an outer end, the outer end extending away from the ear of a wearer when the earplug is inserted in the ear. The earplug can have a first chamber with a first opening, the first chamber positioned between the inner end and the outer end of the earplug. The first chamber can be adapted to receive external sound through the first opening. The earplug can also include a second chamber with a second opening. The second chamber can be positioned between the first chamber and the outer end and adapted to receive sound from the first chamber through the second opening. The earplug can also include a central column extending from the inner end towards the outer end along a longitudinal axis of the earplug. The central column can include a hollow sound channel and a third opening allowing sound from the second chamber to enter into the sound channel. In some aspects, the earplug directs sound through the sound channel towards the ear of the wearer.
The present technology also presents methods of attenuating sound within the ear canal. In certain embodiments, the method includes inserting an earplug into an ear canal of a wearer. The earplug can be one of the earplugs described in accordance with one or more embodiments of the present disclosure. For example, the earplug can have an inner end that faces the ear of the wearer, and an exterior end that faces away from the ear of the wearer. In certain aspects, the method includes directing external sound into a first chamber of the earplug, directing sound from the first chamber away from the ear of the wearer into a second chamber of the earplug, and directing sound from the second chamber, into a sound channel, and towards the ear of the wearer.
Certain embodiments of the present disclosure also describe an earplug assembly. The earplug assembly can comprise a first and second earplug, and a connector cord connecting the earplugs. In some embodiments, the connector cord comprises a first strand attached to the first earplug at a plug end of the strand and a second strand attached to the second earplug at a plug end of the strand. The connector cord can also include a first adjustment slider attached to a slider end of the first strand. The first adjustment slider can have at least one through hole. The connector cord can also include a second adjustment slider attached to a slider end of the second strand. The second adjustment slider can also have at least one through hole. In some embodiments, the first strand passes through and is freely slideable within a through hole of the second adjustment slider. In some aspects of the present technology, the second strand passes through and is freely slideable within a through hole of the first adjustment slider.
Some embodiments of the present technology provide an earplug assembly comprising two earplugs. In some embodiments, each earplug includes a central column extending from an inner column tip to an outer column face. The central column can have a hollow sound channel and a column opening. In some embodiments, the earplug also has an inner platform extending radially from the central column. The inner platform can comprise one or more inner platform openings. The earplug can also include an outer platform extending radially from the central column. The outer platform can have one or more one outer platform openings. The earplug can also include a cap having an outer end. In some embodiments, the earplug assembly also includes a connector cord connecting the earplugs. The connector cord can have a first strand attached to the first earplug at a plug end of the strand and a second strand attached to the second earplug at a plug end of the strand. The connector cord can also include a first adjustment slider attached to a slider end of the first strand. The first adjustment slider can have at least one through hole. The connector cord can also include a second adjustment slider attached to a slider end of the second strand. The second adjustment slider can also have at least one through hole. In some embodiments, the first strand passes through and is freely slideable within a through hole of the second adjustment slider. In some aspects of the present technology, the second strand passes through and is freely slideable within a through hole of the first adjustment slider.
The present technology relates to high fidelity earplugs. More specifically, the present disclosure describes compact earplugs that provide approximately uniform sound attenuation across a wide array of frequencies. Even more particularly, the present technology describes ready-to-wear earplugs that are more compact (i.e., shorter in length) than previous high fidelity length resonance earplugs, thereby providing aesthetic, functional, and other practical benefits.
The present technology provides an earplug that is shorter than the ER20 earplug, while offering similar or improved attenuation properties. The earplugs of the present technology can be used with a 3-flange eartip, for example, the 3 flange eartips described in the '967 patent. The present technology also implements similar mechanical and/or acoustical properties of the sound-conducting stem described in the '967 patent, which can be designed to operate effectively with the 3-flange eartips. The present technology provides these features while offering an earplug that is shorter in length. As such, the presently described earplugs extend to a lesser amount out (or even not at all) out of the ear of a wearer. The present technology also provides systems and methods for producing earplugs at a lower cost than for that of the ER20 earplugs.
The present technology also provides a connector cord that allows for two earplugs to be connected together for wearing and storage.
As described herein, the ER20 earplug described in the '967 patent uses damping techniques and length resonance to provide sound attenuation that offers hearing protection for wearers, without inhibiting the quality of sound delivered into the ear canal. The ER20 earplug reduces the pressure level of sound entering the wearer's ear, but it provides a relatively uniform attenuation across a wide range of sound frequencies. That is, the ER20 earplug allows a wearer to reduce the level of sound entering the ear canal relatively evenly across a wide spectrum of sound frequency or pitch levels. In this manner, a wearer can be able to provide protection to the ears without having to struggle to perceive sounds at a certain frequencies.
For example, factory workers may have previously been forced to choose between providing no sound attenuation (i.e., wearing no ear protection), or providing too much sound attenuation while risking the chance of missing out on important factory sounds, such as warning signals, improperly operating equipment, approaching vehicles, or talking co-workers. Prior to the ER20, such a worker may have considered using an attenuator such as earmuff drilled with one or more holes, or a foam earplug only partially inserted in the ear. The relatively uniform attenuation provided by the ER20 earplug helped alleviate this problem
The ER20 earplugs, however, have a relatively long length. In order to produce the relatively uniform and accurate attenuation, the ER20 earplug operates in a manner that seeks to replicate the normal external-ear resonance of the ear canal, concha, and pinna at an attenuated level. This external-ear resonance occurs at about 2.7 kHz in an average, normal ear.
To replicate this resonance, the ER20 earplugs incorporate a “re-entry horn” feature. The re-entry horn of the ER20 provides a resonance that can be calculated by the formula f=86/L, where L is measured in millimeters (mm) and f is provided in kHz. In order to provide a quarter-wave resonance of about a 2.7 kHz (thereby replicating the resonance of a normal ear), the ER20 earplug utilizes a re-entry horn that is approximately 32 mm in folded length (that is, 2.7 kHz≈86/32 mm). This folded length allows for the earplug to be more compact than if the re-entry horn were an additional 32 mm in length.
In certain situations, however, even this 32 mm re-entry horn can be cumbersome, uncomfortable, and/or not aesthetic or cosmetic. For example, a user that desires to wear a helmet (e.g., a motorcycle helmet) may be unable to wear an ER20 earplug, because the 32 mm re-entry horn can extend beyond the ear, thereby resulting in uncomfortable and/or painful pressure from a tight-fitting helmet.
Additionally, certain users may wish to achieve the same level of high fidelity attenuation, without appearing as though they are wearing earplugs. The re-entry horn of the 32 mm long ER20 earplug can make this difficult, as it is likely to extend beyond the plane of the concha-pinna of the ear, and therefore appear visible to observers.
The present technology provides advantages by providing an earplug that uses two circular chambers or “apartments” in a base section of the earplug. The earplugs of the present technology allow for sound to enter a first chamber through an opening below an inner platform, or “first floor.”
The present technology then directs that sound through one of several openings to a second chamber, defined by the first platform and a second platform, or “second floor.” Once in the second chamber, the sound is directed to flow around the periphery of the second chamber to another opening, or an entrance to a sound channel, or “empty enclosed elevator shaft,” which runs down a central column of the earplug.
The sound channel runs back through the earplug, past the second chamber and the first chamber, then through an acoustic resistance member, and then down a sound-conducting stem into the eartip where it is delivered into the ear canal. By using this round chamber, or “circular apartment” approach as opposed to a re-entry horn approach, the present technology provides an earplug that can be about 6 mm shorter in length overall compared with the ER20 earplug. This reduction in overall length can be sufficient to move the external tip of the earplug inside the plane of the concha-pinna of the ear for many users. This approach offers similar or improved the attenuation frequency response and attenuation characteristics when compared with the longer ER-20 earplugs.
As shown in
As seen in
The outer platform 152, which also includes an outer platform opening 150. The outer platform opening 150 allows sound from the first chamber 140 to enter into a second chamber 160. The second chamber 160 includes a portion of a central column 190, which extends through the center of the base section along the longitudinal axis of the earplug. The size of the first and second chamber can vary. For example, in certain embodiments, the first chamber can have an inner diameter of about 0.136″, an outer diameter of about 0.336″, and a depth of about 0.107″, and a volume of about 0.008 cubic inches. In certain embodiments, the second chamber can have an inner diameter of about 0.220″, an outer diameter of about 0.336″, a depth of about 0.116″, and a volume of about 0.006 cubic inches.
The central column 190 extends from an inner column tip 120 towards an outer column face 195, which can be adjacent to the exterior end 112 of the earplug 10. In some embodiments, the outer face 195 of the central column can comprise symbols, letter, or numbers to identify certain functionality of the earplug. For example, in
A hollow sound channel 180 runs through the central column 190 along the longitudinal axis of the column. In some aspects, the central column 190 has a stem portion 192 that is configured to connect with an eartip 50. The stem 192 can comprise a flange or a collar 194 that provides a friction-tight fit for installation of a flexible eartip 50. For example, the central column 190 can be configured so that a flexible eartip 50 (as shown in
The central column 190 can also comprise a third opening 170, which allows sound from the second chamber 160 to enter into the sound channel 180. In certain embodiments, the third opening 170 is positioned such that sound entering the second chamber 160 is directed around a majority of the central column 190 before entering into the sound channel 180 of the central column.
In certain embodiments, the cap 110 and the exterior end 112 of the cap 110 redirects the sound back towards the ear of a wearer. That is, the sound is then directed around the circumference of the central column 190 into the third opening 170 of the central column. The second opening and the third opening can be positioned such that the sound must travel 180 degrees or more around the central column 180 before reaching the third opening 170. The openings may be positioned such that sound must travel 270 degrees or more around the central column 190 before reaching the third opening 170.
Sound entering the third opening then proceeds through the sound channel (shown as 180 in
In some aspects, the sound channel can comprise an acoustic resistance member 125 (see
The dimensions of the central column 190 and the sound channel 180 and components of the earplug can vary depending on the length of the earplug, and the value of the attenuation. For example, in certain embodiments, the sound channel 180 can have an inner diameter of about 0.080″, and a length of about 0.450″. In certain aspects, the inner diameter of the sound channel can be about 1.5 times smaller than the inner diameter of the first chamber 140.
In use, the base section 100 of the earplug sits at or around the floor of the concha of a wearer's ear. The sound pressure at that the floor of the concha of an ear is typically increased relative to the sound arriving at the ear as a result of the resonances of the concha and pinna of the ear. Accordingly, the present technology reduces this sound pressure by directing sound from around the base of the earplug thru the openings (e.g., 130 and 150), into the first and second chambers (e.g., 140 and 160), around the central column 190, into the sound channel 180 and towards the ear. This redirection of sound results in a reduction in sound pressure level entering the ear canal, while maintaining a relatively high sound quality and clarity across a broad range of sound frequencies.
In certain embodiments of the present technology, the earplug 10 can comprise a pull string or a pull cord. The pull cord can be used, for example, to facilitate removal of the earplug from the ear. The pull cord can have particular value with the earplug of the present technology, which, depending on individual fit, may be difficult for a user to grasp for removal due to the shortened length.
Similarly,
Tests were conducted to record the response to sounds of various frequencies in an open ear, an ear protected with the ER20 earplug, and an ear protected with an earplug of the present technology. The tests used a KEMAR manikin, which is an acoustic manikin with structural features representing the anatomical dimensions an average person. In particular, the KEMAR manikin represents a person with an ear containing acoustic chambers that, in total, provide a similar, or essentially the same acoustic load as an average normal human ear. (For more specifics about the manikin measurements, see: Proceedings of a conference; MD Burkhard 1978, republished by G.R.A.S.)
More specifically,
The present technology also provides an adjustment slider for a connector cord. For example, a connector cord can be used to connect two earplugs such that the earplugs can remain connected when not in use. The connector cord can be designed to be placed over the neck and/or shoulders of a wearer when not in use. The connector cord can also be of an adjustable length, so that a wearer can increase or decrease the distance between the connected earplugs, for example, to accommodate for different head and/or ear sizes of different users.
In certain embodiments, the cord 520 material can be a stretchable cord, for example, using a product like Stretch® Magic. The stretchable cord allows the strand to flex and stretch in an elastic manner, without breaking or tearing, for example. The cord 520 can vary in thickness, for example, the cord can be approximately 0.7 mm to 1.5 mm in thickness.
The user can increase or decrease the distance between the earplugs by sliding one or both ends of the strands 530 and 531 through the adjustment sliders 540 and 541, thereby increasing or decreasing the overall length of the cord 520. For example, to lengthen the cord 520, a user can grasp the cord 520 at either end and pull to a desired length. Conversely, to shorten the cord 520, the user can pull the adjustment sliders 540 and 541 apart from one another.
The present technology also provides methods of attenuating sound within the ear canal.
At step 720, sound is directed into a first chamber of the earplug, for example, through one or more openings in a platform of the earplug. The first chamber can be defined, for example, by the first platform and a second platform.
At step 730, sound is directed from the first chamber into a second chamber of the earplug. For example, the sound can be directed from the first chamber, away from the ear of the wearer, through a second opening in the second platform.
At step 740, sound is directed around a central column of the earplug within the second chamber. In certain embodiments, the second chamber is defined by a cap and the second platform. The central column can have, for example, an opening or an entrance, which leads to the hollow interior portion of the central column, or a sound channel. In certain embodiments, sound is directed at least 180 degrees around the central column of the earplug before directing the sound into the third opening.
At step 750, sound is directed into the sound channel via the opening into the sound channel, and back towards the ear of the wearer. In certain embodiments, the sound is directed through the center or middle of the earplug, past the second chamber and first chamber, and through the center of a stem of the earplug. In certain embodiments, sound is then directed through an eartip, for example, a flexible triple-flange eartip, and into the ear canal of a wearer.
The present technology has now been described in such full, clear, concise and exact terms as to enable any person skilled in the art to which it pertains, to practice the same. It is to be understood that the foregoing describes preferred embodiments and examples of the present technology and that modifications may be made therein without departing from the spirit or scope of the invention as set forth in the claims. Moreover, while particular elements, embodiments and applications of the present technology have been shown and described, it will be understood, of course, that the present technology is not limited thereto since modifications can be made by those skilled in the art without departing from the scope of the present disclosure, particularly in light of the foregoing teachings and appended claims. Moreover, it is also understood that the embodiments shown in the drawings, if any, and as described above are merely for illustrative purposes and not intended to limit the scope of the invention, which is defined by the following claims as interpreted according to the principles of patent law, including the Doctrine of Equivalents. Further, all references cited herein are incorporated in their entirety.
This application makes reference to, and claims priority to U.S. Provisional Patent Application No. 61/866,299 filed on Aug. 15, 2013, titled “Compact High Fidelity Earplug.” U.S. Non-Provisional Patent Application No. 61/866,299 is hereby incorporated by reference in its entirety.
Number | Date | Country | |
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61866299 | Aug 2013 | US |