Wax management system
11140498 · 2021-10-05
Assignee
Inventors
- Michael Barrett (Campbell, CA, US)
- Manny Ocano (Santa Cruz, CA, US)
- Daniel Shen (Palo Alto, CA, US)
- Iain Butler (Santa Cruz, CA, US)
- Florent Michel (Annemasse, FR)
- Raphael Michel (Palo Alto, CA)
- Keith Wong (San Francisco, CA, US)
Cpc classification
H04R2460/17
ELECTRICITY
H04R25/656
ELECTRICITY
International classification
Abstract
A guard for a space access device is configured to output air flow through a distal end portion thereof. The guard includes q housing having a proximal end opening, a distal end opening, and a filter portion positioned between the proximal and distal end openings. The filter includes a first plate having a first opening therethrough and a second plate having a second opening therethrough. When the first plate is overlaid in contact with the second plate, this forms an aperture that extends through both the first and second plates.
Claims
1. A guard for a space access device configured to output air flow through a distal end portion thereof, said guard comprising: a housing having a proximal end opening and a distal end opening, wherein said proximal end opening is configured to be placed nearer than said distal end opening to the output of air flow from the distal end portion of the space access device; and a filter portion positioned in said housing between said proximal and distal end openings, said filter portion comprising: a distal surface, a proximal surface and a thickness, a first opening formed in said distal surface and extending into a first portion of said thickness; and a second opening formed in said proximal surface and extending into a second portion of said thickness; wherein said first opening overlays said second opening to form an aperture that extends through said thickness; wherein said first opening has a first cross-sectional area, said second opening has a second cross-sectional area and said aperture has a third cross-sectional area; and wherein said first cross-sectional area is greater than said third cross-sectional area and said second cross-sectional area is greater than said third cross-sectional area; said guard attached to a securing mechanism, said securing mechanism comprising: a base comprising a longitudinal axis and an outer surface; and an adjustable securing mechanism disposed on at least a portion of said base, said securing mechanism being configured to contact a surface of an internal space or opening into which said securing mechanism is inserted; said adjustable securing mechanism being configured for positioning and maintaining said base at a distance from a location along the internal space or opening; and wherein a least a portion of said adjustable securing mechanism being configured to transition from a first state to a securing state when inserted into the internal space or opening, said securing state comprising at least a portion of said adjustable securing mechanism being constrained to have a smaller cross-sectional diameter relative to a cross-sectional diameter in said first state; and wherein said adjustable securing mechanism comprises a plurality of members configured to contact a wall of the internal space.
2. The guard of claim 1, wherein a perimeter of said aperture is formed by a first perimeter portion formed by a portion of a perimeter of said first opening and a second perimeter portion formed by a portion of a perimeter of said second opening.
3. The guard of claim 2, wherein said perimeter of said aperture is completely formed by said first and second perimeter portions, and wherein each of said first and second perimeter portions are continuous portions.
4. The guard of claim 2, wherein said first and second perimeter portions are on adjacent, parallel, but different planes, so that the said aperture is not formed by a tubular or other enclosed structure on any one plane parallel or coplanar with the parallel planes of said first and second perimeter portions.
5. The guard of claim 1, comprising a plurality of said first openings formed in said distal surface, a plurality of said second openings formed in said proximal surface, and a plurality of said apertures formed by said plurality of first openings overlaying said plurality of second openings, respectively.
6. The guard of claim 5, wherein said plurality of first openings are provided in a plurality of rows and a plurality of columns.
7. The guard of claim 5, wherein said plurality of first openings and said plurality of second openings are provided in waffle patterns in said distal and proximal surfaces, respectively, and wherein said first openings are offset from said second openings to form said apertures.
8. The guard of claim 1, wherein a smallest cross-sectional dimension of said first opening is at least twice as great as a largest cross-sectional dimension of said aperture and a smallest cross-sectional dimension of said second opening is at least twice as great as said largest cross-sectional dimension of said aperture.
9. The guard of claim 1, further comprising a berm circumscribing said filter portion and extending toward a distal end of said guard.
10. The guard of claim 1, wherein said space access device comprises an in-the-ear hearing aid.
11. The guard of claim 1, wherein said space access device comprises an earpiece speaker.
12. The guard of claim 1, wherein said securing mechanism is attached to said space access device.
13. The guard of claim 1, wherein said securing mechanism further comprises a sound blocking portion disposed on at least a portion of said base, said sound blocking portion being configured to seal circumferentially around the surface of the internal space or opening.
14. The guard of claim 13, wherein said adjustable securing mechanism is configured to allow external sound to be transmitted therepast when said securing mechanism is secured in the internal space or opening and said sound blocking portion is configured to prevent external sound to be transmitted therepast when said securing mechanism is secured in the internal space or opening.
15. The guard of claim 13, wherein said sound blocking portion comprises a dome fixed to a distal end portion of said base.
16. The guard of claim 13, wherein said sound blocking portion comprises: a second plurality of members, at least some of said members comprising at least one of: bristles, protrusions, ridges, grooves, blades, bubbles, hooks and tubes; and skirting, wherein said skirting is integrated in spaces between at least some of said second plurality of members.
17. The guard of claim 13, wherein said skirting is integrated with at least two rows of said second plurality of members, and locations along which said portions of said skirting overlap one another in one of said at least two rows are offset from locations along which said portions of said skirting overlap one another in another of said at least two rows.
18. The guard of claim 1, wherein said adjustable securing mechanism is configured to allow external sound to be transmitted therepast when said securing mechanism is secured in the internal space or opening.
19. A guard for a space access device configured to output air flow through a distal end portion thereof, said guard comprising: a housing having a proximal end opening and a distal end opening, wherein said proximal end opening is configured to be placed nearer than said distal end opening to the output of air flow from the distal end portion of the space access device; and a filter portion positioned in said housing between said proximal and distal end openings, said filter portion comprising: a distal surface, a proximal surface and a thickness, a first opening formed in said distal surface and extending into a first portion of said thickness; and a second opening formed in said proximal surface and extending into a second portion of said thickness; wherein said first opening overlays said second opening to form an aperture that extends through said thickness; wherein said first opening has a first cross-sectional area, said second opening has a second cross-sectional area and said aperture has a third cross-sectional area; wherein said first cross-sectional area is greater than said third cross-sectional area and said second cross-sectional area is greater than said third cross-sectional area; wherein a perimeter of said aperture is completely formed by a first perimeter portion formed by a portion of a perimeter of said first opening and a second perimeter portion formed by a portion of a perimeter of said second opening; and wherein said first and second perimeter portions are continuous portions.
20. The guard of claim 19, comprising a plurality of said first openings formed in said distal surface, a plurality of said second openings formed in said proximal surface, and a plurality of said apertures formed by said plurality of first openings overlaying said plurality of second openings, respectively.
21. The guard of claim 20, wherein said plurality of first openings are provided in a plurality of rows and a plurality of columns.
22. The guard of claim 20, wherein said plurality of first openings and said plurality of second openings are provided in waffle patterns in said distal and proximal surfaces, respectively, and wherein said first openings are offset from said second openings to form said apertures.
23. The guard of claim 19, wherein said first and second perimeter portions are on adjacent, parallel, but different planes, so that the said aperture is not formed by a tubular or other enclosed structure on any one plane parallel or coplanar with the parallel planes of said first and second perimeter portions.
24. The guard of claim 19, wherein a smallest cross-sectional dimension of said first opening is at least twice as great as a largest cross-sectional dimension of said aperture and a smallest cross-sectional dimension of said second opening is at least twice as great as said largest cross-sectional dimension of said aperture.
25. The guard of claim 19, further comprising a berm circumscribing said filter portion and extending toward a distal end of said guard.
26. The guard of claim 19, wherein said space access device comprises an in-the-ear hearing aid.
27. The guard of claim 19 attached to a securing mechanism, said securing mechanism comprising: a base comprising a longitudinal axis and an outer surface; and an adjustable securing mechanism disposed on at least a portion of said base, said securing mechanism being configured to contact a surface of an internal space or opening into which said securing mechanism is inserted; said adjustable securing mechanism being configured for positioning and maintaining said base at a distance from a location along the internal space or opening; and wherein a least a portion of said adjustable securing mechanism being configured to transition from a first state to a securing state when inserted into the internal space or opening, said securing state comprising at least a portion of said adjustable securing mechanism being constrained to have a smaller cross-sectional diameter relative to a cross-sectional diameter in said first state; and wherein said adjustable securing mechanism comprises a plurality of members configured to contact a wall of the internal space.
28. The guard of claim 27, wherein said securing mechanism further comprises a sound blocking portion disposed on at least a portion of said base, said sound blocking portion being configured to seal circumferentially around the surface of the internal space or opening.
29. The guard of claim 28, wherein said adjustable securing mechanism is configured to allow external sound to be transmitted therepast when said securing mechanism is secured in the internal space or opening and said sound blocking portion is configured to prevent external sound to be transmitted therepast when said securing mechanism is secured in the internal space or opening.
30. The guard of claim 28, wherein said sound blocking portion comprises a dome fixed to a distal end portion of said base.
31. The guard of claim 28, wherein said sound blocking portion comprises: a second plurality of members, at least some of said members comprising at least one of: bristles, protrusions, ridges, grooves, blades, bubbles, hooks and tubes; and skirting, wherein said skirting is integrated in spaces between at least some of said second plurality of members.
32. The guard of claim 31, wherein said skirting is integrated with at least two rows of said second plurality of members, and locations along which said portions of said skirting overlap one another in one of said at least two rows are offset from locations along which said portions of said skirting overlap one another in another of said at least two rows.
33. The guard of claim 27, wherein said adjustable securing mechanism is configured to allow external sound to be transmitted therepast when said securing mechanism is secured in the internal space or opening.
34. A guard for a space access device configured to output air flow through a distal end portion thereof, said guard comprising: a housing having a proximal end opening and a distal end opening, wherein said proximal end opening is configured to be placed nearer than said distal end opening to the output of air flow from the distal end portion of the space access device; and a filter portion positioned in said housing between said proximal and distal end openings, said filter portion comprising: a distal surface, a proximal surface and a thickness, a first opening formed in said distal surface and extending into a first portion of said thickness; and a second opening formed in said proximal surface and extending into a second portion of said thickness, wherein said first opening ends wherein said first portion of said thickness meets said second portion of said thickness and said second opening ends where said second portion of said thickness meets said first portion of said thickness; wherein said first opening overlays said second opening to form an aperture that extends through said thickness; wherein said first opening has a first cross-sectional area, said second opening has a second cross-sectional area and said aperture has a third cross-sectional area; and wherein said first cross-sectional area is greater than said third cross-sectional area and said second cross-sectional area is greater than said third cross-sectional area.
35. The guard of claim 34, wherein a smallest cross-sectional dimension of said first opening is at least twice as great as a largest cross-sectional dimension of said aperture and a smallest cross-sectional dimension of said second opening is at least twice as great as said largest cross-sectional dimension of said aperture.
36. The guard of claim 34, wherein said guard comprises a plurality of said first openings formed in said distal surface, a plurality of said second openings formed in said proximal surface, and a plurality of said apertures formed by said plurality of first openings overlaying said plurality of second openings, respectively; and wherein said plurality of first openings are provided in a plurality of rows and a plurality of columns.
37. The guard of claim 34 attached to a securing mechanism, said securing mechanism comprising: a base comprising a longitudinal axis and an outer surface; and an adjustable securing mechanism disposed on at least a portion of said base, said securing mechanism being configured to contact a surface of an internal space or opening into which said securing mechanism is inserted; said adjustable securing mechanism being configured for positioning and maintaining said base at a distance from a location along the internal space or opening; and wherein a least a portion of said adjustable securing mechanism being configured to transition from a first state to a securing state when inserted into the internal space or opening, said securing state comprising at least a portion of said adjustable securing mechanism being constrained to have a smaller cross-sectional diameter relative to a cross-sectional diameter in said first state; and wherein said adjustable securing mechanism comprises a plurality of members configured to contact a wall of the internal space.
38. The guard of claim 34, wherein a perimeter of said aperture is formed by a first perimeter portion formed by a portion of a perimeter of said first opening and a second perimeter portion formed by a portion of a perimeter of said second opening; and wherein each of said first and second perimeter portions are continuous portions.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) In the course of the detailed description to follow, reference will be made to the attached drawings. These drawings show different aspects of the present invention an, where appropriate, reference numerals illustrating like structures, components, materials and/or elements in different figures are labeled similarly. It is understood that various combinations of the structures, components, materials and/or elements, other than those specifically shown, are contemplated and are within the scope of the present invention.
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DETAILED DESCRIPTION OF THE INVENTION
(25) Before the present devices and methods are described, it is to be understood that this invention is not limited to particular embodiments described, as such may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting, since the scope of the present invention will be limited only by the claims.
(26) Where a range of values is provided, it is understood that each intervening value, to the tenth of the unit of the lower limit unless the context clearly dictates otherwise, between the upper and lower limits of that range is also specifically disclosed. Each smaller range between any stated value or intervening value in a stated range and any other stated or intervening value in that stated range is encompassed within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded in the range, and each range where either, neither or both limits are included in the smaller ranges is also encompassed within the invention, subject to any specifically excluded limit in the stated range. Where the stated range includes one or both of the limits, ranges excluding either or both of those included limits are also included in the invention.
(27) Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although any methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, the preferred methods and materials are now described. All publications mentioned herein are incorporated herein by reference to disclose and describe the methods and/or materials in connection with which the publications are cited.
(28) It must be noted that as used herein and in the appended claims, the singular forms “a”, “an”, and “the” include plural referents unless the context clearly dictates otherwise. Thus, for example, reference to “a dome” includes a plurality of such domes and reference to “the opening” includes reference to one or more openings and equivalents thereof known to those skilled in the art, and so forth.
(29) The publications discussed herein are provided solely for their disclosure prior to the filing date of the present application. The dates of publication provided may be different from the actual publication dates which may need to be independently confirmed.
(30) Definitions
(31) The term “space access device”, as used herein, means a device that is designed and adapted to be inserted into a space or opening, including, but not limited to audio signal transmitting devices, including but not limited to anatomical or biological and non-biological devices that are designed and adapted to be inserted into a space or opening, such as an ear canal, nasal conduit, esophagus, airway, gastro-intestinal tract, blood vessel, pipe, or conduit.
(32) The term “outwardly projecting member”, as used in connection with a securing mechanism of the invention, means and includes any projection extending from a base member, including, without limitation, fins, bristles, blades, protrusions, ridges, grooves, bubbles, balloons, hooks, looped structure, disks and/or tubes.
(33) The term “overlap” as used herein, refers to two objects or portions thereof existing along a straight line or pathway at different locations of the line or pathway. For example, when one portion of a skirt “overlaps” another portion of a skirt, this overlap blocks a pathway in a direction along a longitudinal axis of a securing mechanism/ hearing device. The overlapping portions served to block sound transmission along the pathway where the portions overlap. In some embodiments, the securing members of different rows of securing members overlap one another. In these examples, a restricted airflow pathway typically remains between the overlapping securing members of different rows. In the case of overlapping skirts, the overlapped portions contact one another and do not allow airflow through the contacted, overlapped portions.
(34) The terms “headphone” and “headset” are used interchangeably herein and mean and include a listening device that is adapted to receive transmitted sound via wireless or wired communication means. As is well known in the art, conventional headphones and headsets typically include one or more speakers and/or sound production components, which can be in the form of one or two earpieces (often referred to as “ear plugs” or “ear buds”).
(35) The terms “pharmacological agent”, “active agent”, “drug” and “active agent formulation” are used interchangeably herein, an mean and include an agent, drug, compound, composition of matter or mixture thereof, including its formulation, which provides some therapeutic, often beneficial, effect. This includes any physiologically or pharmacologically active substance that produces a localized or systemic effect or effects in animals, including warm blooded mammals, humans and primates, avians, domestic household or farm animals, such as cats, dogs, sheep, goats, cattle, horses and pigs; laboratory animals, such as mice, rats and guinea pigs; reptiles, zoo and wild animals, and the like. One or more of the components described herein may be coated with or otherwise provided with one or more pharmacological agents.
(36) The terms “pharmacological agent”, “active agent”, “drug” and “active agent formulation” thus mean and include, without limitation, antibiotics, anti-viral agents, analgesics, steroidal anti-inflammatories, non-steroidal anti-inflammatories, anti-neoplastics, anti-spasmodics, modulators of cell-extracellular matrix interactions, proteins, hormones, enzymes and enzyme inhibitors, anticoagulants and/or antithrombotic agents, DNA, RNA, modified DNA and RNA, NSAIDs, inhibitors of DNA, RNA or protein synthesis, polypeptides, oligonucleotides, polynucleotides, nucleoproteins, compounds modulating cell migration, compounds modulating proliferation and growth of tissue, and vasodilating agents.
(37) The following disclosure is provided to further explain in an enabling fashion the best modes of performing one or more embodiments of the present invention. The disclosure is further offered to enhance an understanding of and appreciation for the inventive principles and advantages thereof, rather than to limit in any manner the invention. The invention is defined solely by the appended claims including any amendments made during the pendency of this application and all equivalents of those claims as issued.
(38) As will readily be appreciated by one having ordinary skill in the art, the present invention substantially reduces or eliminates the disadvantages and drawbacks associated with conventional wax management systems for in the ear devices.
(39) In overview, one aspect of the present invention is directed to wax management devices that can be readily employed with devices and systems that are configured to be inserted in one or more biological spaces or openings, such as an ear canal.
(40) Referring now to the drawings,
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(42) Securing mechanism 10c (
(43) The adjustable securing mechanism 10c, 10d, 10e, 10f is disposed on at least a portion of the base 16 and is configured to contact a surface of an internal space or opening into which said securing mechanism 10c, 10d, 10e, 10f is inserted.
(44) The securing portion, by action of the adjustable, outwardly projecting members 20, 40, 120, 130 is configured for positioning and maintaining the base 16 (and a space access device when the securing mechanism is mounted thereon) at a distance from a location along the internal space or opening. Thus, for example, when the securing mechanism is mounted on or attached to an in-ear hearing aid, the adjustable, outwardly projecting members adjust so as to keep the base 16 and the space access securing device located in the internal space or opening so that a distance or gap is provided between the base 16 and the space access device at all locations 360 degrees about the base and space access device.
(45) The securing portion is configured for positioning and maintaining the base and the space access device at a distance from a location such as an end of the internal space or opening. For example, the adjustable securing portion of the securing mechanism 10c, 10d, 10e, 10f may be configured to maintain a distal end of a hearing aid and distal end of the securing mechanism at a predetermined distance relative to the ear drum. As another example, the securing portion of the mechanism 10c, 10d, 10e, 10f may be configured to maintain a proximal end of a hearing aid at a predetermined distance relative to the opening of the ear canal. The securing portion 10c, 10d, 10e, 10f is designed and adapted to conform or self-adjust to the shape of the interior surface of an opening (or interior space) of a member (biological or non-biological) when the securing mechanism (typically, but not necessarily attached to an access device) of the invention and, thereby, the projecting members 20, 40, 120, 130 are inserted in the opening by a tube, such as a tube defining an internal anatomical space. Further details regarding the securing mechanisms 10c, 10d, 10e, 10f can be found in co-pending U.S. Application Serial No. 15/785,731, filed on even date herewith, titled “Adjustable Securing Mechanism” and which is hereby incorporated herein, in its entirety, by reference thereto.
(46) In
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(48) In the embodiment of
(49) Blocking portion 204 may be made of the same material as outwardly projecting members 120 and/or the main body of the securing mechanism, or may be made from a different material selected from any of the materials described previously in this disclosure, including, but not limited to thermoplastic elastomers. Preferably the blocking portion 204, projecting members 120 and main body are all molded from the same material, preferably silicone. The hardnesses of the components may be the same or different and may each be in the range from about 20 durometer Shore A to about 80 durometer Shore A, preferably from about 30 to 60 durometer Shore A. In one example, the components were molded from platinum-cured silicone have a hardness of 60 durometer Shore A. In another example, the components were molded from platinum-cured silicone having a hardness of 40 durometer Shore A. Because the securing portion 202 provides the primary anchoring forces for holding the securing mechanism 10e in place in an inner space or opening, the outside diameter 206 (for a sound blocking portion 204 having a circular cross-section) or largest cross-sectional dimension 206 of the sound blocking portion 204, in a direction normal to the longitudinal axis 15 of the securing mechanism 10e, when in a relaxed configuration as shown in
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(51) In the embodiment of
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(53) For uses where the opening or internal space is larger than the ones for which the embodiment of
(54) Like the embodiment of
(55) To provide an even greater blocking of sound, the embodiments described herein may include more than one dome portion 204 or more than one row of outwardly projecting members 130′ having skirting 306.
(56) The present invention provides wax management systems designed to prevent wax migration into the working components of a hearing aid or other space access device and to help prevent audio degradation of signals provided by the hearing aid or other space access device. In the case of a hearing aid, the hearing aid will typically be provided with a filter, such as filter 69 (
(57) The lumen 18, 248 of the securing mechanism 10c, 10d, 10e, 10f includes an opening 19 that opens to outside of the securing mechanism at the distal end thereof, e.g., see
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(59) The filter portion 1306 of the embodiment shown in
(60) The openings 1314 in plate 1312 are arranged in a regular pattern of rows and columns separated by row spacings of equal heights 1316 and column spacings of equal widths 1318. The openings 1324 in plate 1322 can be of the same size, shape and orientation as those of openings 1314 in plate 1312 and can be separated by row spacings 1318 of equal height which are equal to the heights of row spacings 1316 and by column spacings 1328 of equal width equal to the column spacing widths 1318. However, the positions of openings 1324 on plate 1322 in the X and Y directions (width and height directions), respectively, are offset relative to the positions of the openings 1314 on plate 1312 in the X and Y directions, by a distance in the Y (height) direction equal to the height 1330 of opening 1314 minus the height 1352 of aperture 1350 (see
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(62) Additionally, the cross-sectional dimensions of openings 1314 and 1324 are much greater than the cross-sectional dimensions of the apertures 1350. This results in the walls of the openings 1314 and 1324 being much greater in length and width than the lengths and widths of the apertures, which provides a much greater amount of surface area that is exposed to wax, so that no capillary action occurs relative to the large openings 1312, 1322. Also, the opening perimeters of openings 1312 provide large lengths and widths of surface edges that may interact with the wax preferably and with greater attraction than any that may occur with the underlying perimeters of openings 1322, further preventing migration of wax through apertures 1350. The smallest cross-sectional dimension of opening 1314, 1324 may be at least twice as great as the largest cross-sectional dimension of aperture 1350, or at least three times as great, or at least four times as great or in a range of 1.5 to 12 times as great, preferably in a range from about 3 to 10 times as great, more preferably in a range from about 4 to about 8 times as great. In at least one embodiment, apertures 1350 are rectangular, each having a length of about 0.120 mm and a width of about 0.060±0.025 mm and openings 1312, 1322 are rectangular, each having a length of about 0.41 mm and a width of about 0.28 mm. The thickness of each plate may be in a range from about 0.1 mm to about 1 mm, typically from about 0.2 mm to about 0.5 mm. In one example, the thickness was about 0.25 mm. The cross-sectional area of aperture 1350 is less than 25 percent of the cross-sectional area of opening 1314 or 1324, preferably less than 15 percent, and may be in a range from about 15 percent to about 2 percent, typically from about 10 percent to about 3 percent. In one example the cross-sectional area of aperture 1350 was about 6.27 percent of the cross-sectional area of opening 1314 and about 6.27 percent of the cross-sectional area of opening 1324. In another example, the cross-sectional area of aperture 1350 was about 3.66 percent of the cross-sectional area of opening 1314 and about 3.66 percent of the cross-sectional area of opening 1324. In the embodiments shown, the apertures 1350 are formed in the four corners of the openings 1314, 1324, and portions of the plates 1312, 1314 obstruct the remainders of the openings, as the plate 1312 is overlaid on plate 1324 and the plates are contacted together as described. The distance between apertures 1350 is typically at least two to three times the greatest cross-sectional dimension of the aperture 1350, and may be in a range of 1.25 to about 6 times the greatest cross-sectional dimension, typically in a range of from about 1.75 to about 4 times the greatest cross-sectional dimension. The berm 1308 extends in a direction perpendicular to and away from the plate 1312 by a distance 1308L in a range from about 0.25 mm to about 1.0 mm, typically in a range from about 0.5 mm to about 0.75 mm. This results in a dish-shaped distal end portion of guard 1300, as shown in
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(65) The gutters 420 slope downwardly and outwardly from the gutter inlets 422I to gutter outlets 422E located on the external walls of the guard 400 at locations below the level of the plate 412, as shown in
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(70) Additionally, the cross path 524 may join the sound exit path 526 at an acute angle 530 as shown in
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(72) While the present invention has been described with reference to the specific embodiments thereof, it should be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the true spirit and scope of the invention. In addition, many modifications may be made to adapt a particular situation, material, composition of matter, process, process step or steps, to the objective, spirit and scope of the present invention. All such modifications are intended to be within the scope of the claims appended hereto.