Protection of integrated low power system designed to monitor the acoustic environment
11457299 · 2022-09-27
Assignee
Inventors
Cpc classification
H04R1/44
ELECTRICITY
H04R2410/07
ELECTRICITY
H04R1/28
ELECTRICITY
International classification
H04R1/02
ELECTRICITY
Abstract
Various aspects of the present disclosure are directed toward apparatuses, systems and methods that include an acoustic apparatus. The apparatuses, systems and methods may include an acoustic membrane and a protective housing defining an interior space in which the acoustic membrane is received.
Claims
1. An acoustic apparatus, comprising: an acoustic membrane; a protective housing defining an interior space in which the acoustic membrane is received, the protective housing including indirect pathways extending from outside the protective housing into the interior space of the protective housing to allow acoustic energy from outside the protective housing into the interior space and to the acoustic membrane and the protective housing forming an acoustic gap configured to provide, in combination with the acoustic membrane, a 0.5 dB-20 dB insertion loss in the frequency range from 300 Hz to 5 kHz; and a microphone configured with the acoustic membrane to sense an acoustic signal and arranged within the interior space, wherein the protective housing defines the interior space in which the microphone and the acoustic membrane are received such that the acoustic membrane protects the microphone from exposure to water.
2. The acoustic apparatus of claim 1, wherein the protective housing includes an upper protective housing and a lower protective housing and the acoustic membrane is arranged between the upper protective housing and the lower protective housing and the microphone is arranged within the lower protective housing and the upper protective housing includes one or more openings along an external surface and one or more vanes aligned with the one or more openings, wherein the one or more openings and the one or more vanes form the indirect pathways, and wherein the one or more vanes are configured to direct water spray away from the acoustic membrane.
3. The acoustic apparatus of claim 2, wherein each of the one or more vanes include a curved surface facing the one or more openings and second and third surfaces extending from the curved surface expanding a width of the one or more vanes.
4. The acoustic apparatus of claim 2, further comprising a protective structure that is at least one of wrapped about the external surface of the protective housing and arranged within the interior space of the protective housing, the protective structure being configured to enhance at least one of wind noise and spray protection performance.
5. The acoustic apparatus of claim 2, wherein the upper protective housing and the lower protective housing are configured to interface, and the lower protective housing includes one or more lower openings that are aligned with the openings in the upper protective housing.
6. The acoustic apparatus of claim 5, wherein a first surface of the one or more vanes interfaces with a first surface of the lower protective housing.
7. The acoustic apparatus of claim 6, wherein the first surface of the one or more vanes includes a recessed portion relative to the first surface of the one or more vanes, and the first surface of the one or more vanes is configured to bound the acoustic membrane.
8. The acoustic apparatus of claim 7, wherein the first surface of the lower protective housing includes a first recessed portion and a second recessed portion, and the first recessed portion of the lower protective housing is configured to bound the first surface of the one or more vanes and the second recessed portion of the lower protective housing is configured to bound the acoustic membrane.
9. The acoustic apparatus of claim 2, wherein each of the one or more vanes includes straight surfaces.
10. The acoustic apparatus of claim 1, wherein the microphone is a microelectromechanical systems (MEMS) microphone coupled to a flex circuit arranged within the protective housing.
11. The acoustic apparatus of claim 10, wherein the protective housing includes the acoustic gap between the microelectromechanical systems (MEMS) microphone and the acoustic membrane.
12. The acoustic apparatus of claim 1, wherein the protective housing is configured to exhibit a 0.5 dB-3 dB insertion loss in the frequency range from 300 Hz to 5 kHz.
13. The acoustic apparatus of claim 1, wherein the protective housing is arranged external to a cabin of a vehicle; and the microphone is configured to facilitate interaction with the vehicle.
14. The acoustic apparatus of claim 1, wherein the protective housing is configured to comply with at least one of: International Standard 20653 or International Standard 16750-4 for road vehicles.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) The accompanying drawings are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this specification, illustrate embodiments, and together with the description serve to explain the principles of the disclosure.
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
(13)
(14)
DETAILED DESCRIPTION
(15) Persons skilled in the art will readily appreciate that various aspects of the present disclosure can be realized by any number of methods and apparatus configured to perform the intended functions. It should also be noted that the accompanying drawing figures referred to herein are not necessarily drawn to scale, but may be exaggerated to illustrate various aspects of the present disclosure, and in that regard, the drawing figures should not be construed as limiting.
(16) Various aspects of the present disclosure are directed toward protective housings that are exposed to more aggressive ambient conditions, such as those experienced on the exterior of vehicles, under extreme weather conditions, or which might otherwise be encountered. The housings may be provided to protect sensors, acoustic transducers, microphones or other electronic elements. The sensors, acoustic transducers, microphones or other electronic elements may be manufactured separately from the protective housings and added to the housing separately. The sensors or acoustic transducers can provide a variety of functions, such as communication with on board electronics. For example, an owner or other individual may wish to issue voice commands or prompts to the vehicle when the owner or other individual is external to the vehicle. This may include commanding or prompting the vehicle to lock, start, or perform another function. In addition, the sensors or acoustic transducers may also sense other sounds external to the vehicle (e.g., emergency vehicle sirens, oncoming traffic).
(17) With the sensors or acoustic transducers being arranged external to the vehicle or otherwise exposed to the elements, the sensors or acoustic transducers require protection from various environmental factors, including high velocity rain and atomized water particles, debris, and other elements. Various examples of protective housings (or acoustic microphone apparatuses) addressed in this disclosure generally protect against elements external to a vehicle without unacceptable degradation of an acquired acoustic signal or pressure. For vehicular use, the sensors or acoustic transducer assemblies may require compliance, or it may simply be desirable that the assemblies comply with certain international standards (e.g., International Standard (ISO) 20653: Road Vehicles—Degrees of Protection (IP Code)—Protection of electrical equipment against foreign objects, water, and access; 2.sup.nd Edition (2013) and ISO 16750-4: Road vehicles—Environmental conditions and testing for electrical and electronic equipment—Part 4: Climatic loads; 3.sup.rd Edition (2010)) or country-based standards. ISO 20653 describes various degrees of protection against foreign objects/access and against water (e.g. IPx6K and IPx9K tests). ISO 16750-4 describes potential environmental stresses and specifies tests (e.g., thermal cycling test IEC 60068 2-14) and requirements for the specific mounting locations of electronic components with respect to road vehicles to protect the electronic components against climatic loads.
(18)
(19) In addition, sensors or acoustic transducers may be arranged at locations external to the vehicle 100 other than the sensor/microphone locations 102a-e shown. The sensors or acoustic transducers may be arranged within a housing, which is arranged within an external portion of the vehicle 100 or a portion of the vehicle 100 likely to be exposed to the elements. The housings (not shown) may be arranged such that an external surface of the housing is flush or even with an external or other surface of the vehicle 100.
(20)
(21) The vane 204, which may be an integral part of the housing 202, forms an indirect pathway for flow 206 of environmental elements. In certain instances, the indirect pathway formed by the vane 204 (and housing 202) lessens the opportunity for elements to impair the functionality of the acoustic transducer or sensor 208 by impinging on a membrane and/or the transducer or sensor 208. The vane 204 (and housing 202) may be configured to protect the acoustic transducer or sensor 208 from a water spray test and allow the acoustic signal to excite the acoustic transducer or sensor 208 without noticeable degradation of the acoustic signal. The material of the vane 204 may be altered or tailored to a use or location (e.g., external to a vehicle) to enhance or improve noise performance.
(22) As shown in
(23) The acoustic apparatus 200 shown in
(24)
(25) The acoustic apparatus 200 may also include an acoustic membrane 304 and an electronic component 306 (e.g., a microphone, sensor). The electronic component 306 configured with the acoustic membrane 304 to sense an acoustic signal. The protective housing 300, 302 is configured to protect the membrane 304 and electronic component 306 from a water spray test (International Standard (ISO) 20653: Road Vehicles—Degrees of Protection (IP Code)—Protection of electrical equipment against foreign objects, water, and access or other country-based standards). The protective housing 300, 302 is also configured to form an acoustic gap providing, in combination with the membrane 304, a desired acoustic performance (e.g., 0.5 dB-20 dB insertion loss in the frequency range from 300 Hz to 5 kHz), as is discussed in further detail with reference to
(26) In certain instances, the protective housing 300, 302 may include an upper protective housing 300 and a lower protective housing 302. As shown in
(27) In addition, the electronic component 306 may be a microelectromechanical systems (MEMS) microphone 308 coupled to a flex circuit 310 that may be arranged within the protective housing 300, 302. As shown in
(28) The acoustic apparatus 200 optionally includes a gasket 314 between the lower protective housing 302 and the electronic component 306. In certain instances and in lieu of or in addition to the gasket 314, the electronic component 306 may be adhered to the upper protective housing 300 or the lower protective housing 302. In addition, the upper protective housing 300 and/or the lower protective housing 302 may be overmolded directly to or about the electronic component 306. The gasket 314 may facilitate acoustic performance of the electronic component 306, assist with sealing the microphone 308 against ingress of moisture, aid to prevent vibration or shock damage to the microphone 308, or provide additional or alternative functions as desired. The gasket 314 may be formed of silicone or another similar low durometer material. In addition, the acoustic apparatus 200 may include a base portion 318 that is arranged about the flex circuit 310 below the microphone 308 and attached to the lower protective housing 302. The base portion 318 may be configured to help protect the microphone 308 from the elements, as is discussed in further detail with reference to
(29)
(30) As shown in
(31) As explained in further detail with reference to
(32) Indirect pathways 452, formed by the vanes 204a-d, for the environmental elements extend from the external surface 420. Openings 422a-d in the upper protective housing 300 may be an entry point for the indirect pathways 452 (formed by the housing 300, 302 and the vanes 204a-d). The openings 422a-d may be equal in number to the vanes 204a-d. In addition, the openings 422a-d allow for environmental elements and acoustic pressure waves to enter the protective housing 300, 302. In certain instances, the vanes 204a-d are aligned with the openings 422a-d. The vanes 204a-d are configured to direct the environmental elements (e.g., water spray) away from the membrane 304 arranged within the protective housing 300, 302. The vanes 204a-d are arranged to prevent direct impingement of environmental elements (e.g., water spray) on the membrane 304. In certain instances, the openings 422a-d are the only access point for environmental elements to enter the protective housing 300, 302. Thus, the environmental elements (e.g., water spray, or atomized water particles) directly contact the vanes 204a-d upon entry into the protective housing 300, 302. As a result, the elements of the protective housing 300, 302 (e.g., vanes 204a-d, openings 422a-d) form the indirect pathways 452 (shown in
(33)
(34) In instances where the one or more vanes 204a-d includes multiple vanes 204a-d, gaps 434a-d are between the vanes 204a-d. In addition, and as shown in
(35)
(36) An example of flow 206 of environmental elements is shown in
(37) In certain instances, an angle created by the indirect pathways 452 is formed to permit atmospheric and acoustic pressure into the protective housing 300, 302. In addition, the vanes 204a-d may be sized to create the indirect pathways 452 to permit atmospheric and acoustic pressure into the protective housing 300, 302 while also protecting the membrane 304 and electronic component 306 from the water and other environmental elements.
(38)
(39) In certain instances, the lower protective housing 302 includes one or more lower openings 540a-d. The lower openings 540a-d in the lower protective housing 302 can be aligned with the openings 422a-d in the upper protective housing 300. Upon assembly, the sets of openings 422a-d, 540a-d combine to define openings in the protective housing 300, 302 formed by the integration of the upper protective housing 300 and the lower protective housing 300.
(40) In certain instances, the lower protective housing 302 includes first surface 542. The lower protective housing 302 includes first extensions 544a-d extending perpendicular to and from the first surface 542 of the lower protective housing 302. The extensions 544a-d are configured to protect the internal elements (e.g., a membrane 304) of the protective housing 300, 302. In addition, the extensions 544a-d provide an external surface 546 of the lower protective housing 302 with the lower openings 540a-d being through the external surface 546 of the lower protective housing 302.
(41) The first surface 436a-d of the vanes 204a-d may be configured to interface with the first surface 542 of the lower protective housing 302. In addition, the first surface 542 of the lower protective housing 302 includes a first recessed portion 548a-d and a second recessed portion 550. The first recessed portion 548a-d, in certain instances, are complimentary to the vanes 204a-d. The first recessed portion 548a-d bounds the vanes 204a-d and may be configured to facilitate integration between the upper protective housing 300 and the lower protective housing 302. In addition, and similar to the recessed portion 438a-d of the vanes 204a-d, the second recessed portion 550 is configured to bound the membrane 304. The recessed portion 438a-d of the vanes 204a-d and the second recessed portion 550 may be configured to facilitate protection of the membrane 304 by partially or surrounding the edges of the membrane 304.
(42)
(43) The second extensions 552a-d surround a second surface 556 of the lower protective housing 302. As discussed in further detail with reference to
(44)
(45)
(46)
(47) In certain instances, the frequency range may be 300 Hz to 3 kHz for these insertion losses. In some instances, a high level of attenuation may be desirable (e.g., up to 20 dB) such as in noisy environments where a microphone may have difficulty processing high pressures (e.g., passive attenuation). The acoustic gap 660 may be sized to exhibit a 0.5 dB-20 dB insertion loss in the frequency range from 300 Hz to 5 kHz. The acoustic gap 660 may also be sized to exhibit a 0.5 dB-20 dB insertion loss in the frequency range from 300 Hz to 10 kHz. As a result, the acoustic gap 660 does not audibly degrade the acoustic performance of the membrane 304 and the electronic component 306.
(48) As referenced, the electronic component may be a microelectromechanical systems (MEMS) microphone 308 coupled to a flex circuit 310 that may be arranged within the protective housing 300, 302. The microphone 308 (or other electronic components such as sensors, acoustic transducers) may be integrated into the acoustic apparatus 200 after manufacture of the acoustic apparatus 200. For example, an end user of the acoustic apparatus 200 may insert the microphone 308 (or other electronic components such as sensors, acoustic transducers) into the acoustic apparatus 200 prior to use.
(49) The acoustic gap 660 may be arranged between the MEMS microphone 308 and the acoustic membrane 304. The acoustic gap 660 may be between 1 mm and 15 mm, in certain instances, and may include a volume (e.g., 0.8 mm.sup.3-30 mm.sup.3) that has 0.5 dB-20 dB insertion loss in the target frequency range (e.g., from 300 Hz to 5 kHz, from 300 Hz to 10 kHz, among others). In certain instances, a length (and volume) of the acoustic gap 660 may be modified to accommodate certain situations or installations. The length may be increased by extending an interior length 664 of the lower protective housing 302. The membrane 304 may be adhesively secured, heat welded, laser welded, ultrasonically welded, or otherwise coupled to the lower protective housing 302, for example. In addition, the acoustic gap 660 behind the membrane 304 is sealed. In addition, the acoustic apparatus 200 may include a gasket 314 arranged between the lower protective housing 302 and the electronic component 306. The gasket 314, and membrane 304, may equalize the atmospheric pressure within the gap 660. In certain instances, a protective structure (e.g., polytetrafluoroethylene (PTFE), polytetrafluoroethylene expanded (ePTFE), a woven fiber structure such as cotton fiber, a foam such polyurethane foam, a polyester woven material, porous metal, or other similar structures) may fill the interior 432 between the vanes 204a-d. The protective structure may be configured to enhance wind noise and/or spray protection performance of the acoustic apparatus 200. In addition or alternatively to the protective structure being arranged within the interior 432, the protective structure may be wrapped about an external surface 662 of the protective housing 600. For example, the protective structure may be a sheet of material wrapped about or covering the external surface 662 of the protective housing 600. The protective structure may be configured to enhance wind noise and/or spray protection performance of the acoustic apparatus 200.
(50) In certain instances, the protective housing 600 includes indirect pathways 452 (shown in
(51) The housing 600 may also protect against environmental elements by removing energy from atomized water particles that are under pressure while permitting the gap 660 to remain at or near atmospheric pressure. The housing 600 and, in particular the indirect pathways 452, being configured in this manner may facilitate protection of the membrane 304 without noticeable degradation of the acoustic signal.
(52) Openings 658a-b in the protective housing 600 provide an entry point for the indirect pathways and for the environmental elements and acoustic signal or signal to enter the protective housing 600. The openings 658a-b (formed by openings 422a-d in the upper protective housing 300 and lower openings 540a-d in the lower protective housing 302 aligned with the openings 422a-d in the upper protective housing 300) may be an entry point for the indirect pathways 452 (shown in
(53) The openings 658a-b may be equal in number to the vanes 204a-d. In certain instances, the vanes 204a-d are aligned with the openings 658a-b. The vanes 204a-d are configured to direct the environmental elements (e.g., wind, water spray, particulate, or other contaminants) away from the membrane 304 arranged within the protective housing 600. The vanes 204a-d are arranged to prevent direct impingement of environmental elements (e.g., water spray) on the membrane 304. In certain instances, the openings 658a-b are the only access point for environmental elements to enter the protective housing 600. Thus, the environmental elements (e.g., wind, water spray, particulate, or other contaminants) directly contact the vanes 204a-d upon entry into the protective housing 600.
(54)
(55) As noted above, the first recessed portion 548a-d of the lower protective housing 302 may bound the vanes 204a-d and may be configured to facilitate integration between the upper protective housing 300 (not shown in
(56) In certain instances, the protective housing 600 is arranged external to a cabin of a vehicle as shown in
(57) As the term is used herein, “gasket” and derivations thereof shall mean a material having properties of absorbing or reflecting sound and vibration wave energy when compressed between two surfaces to form a seal. The gasket can be used in a conventional manner between a transducer/MEM microphone and a housing surface, or between surfaces within a housing, to acoustically isolate and dampen vibrations in selected areas.
(58) The protective housing discussed herein may be injection-molded. Vulcanizable plastics, such as silicones or natural rubber, and thermoplastics, such as polypropylene, polyethylene, polycarbonates or polyamides, as well as preferably thermoplastic elastomers, like Santoprene™. or Hytrel™. All these plastics can be used in the so-called insert molding injection-molding process, which offers the significant advantage that it is possible to injection-mold the protective housing to the membrane 304 in one work process. The thermoplastic elastomers can combine the properties of being able to be processed in the insert molding injection-molding process and preserving their elastomer properties in so doing. In addition, the protective housing may be formed of a hydrophobic or hydrophilic material or may include a hydrophobic or hydrophilic coating. The hydrophilic material or coating facilitates draining of water by, for example being configured to allow water to stick to the vanes (formed of the hydrophilic material or having a hydrophilic coating) such that water does not run into and onto the membrane. The hydrophobic material or coating facilitates repelling of water by, for example, the vanes (formed of the hydrophobic material or having a hydrophilic coating) repelling water such that the water does not run into and onto the membrane. The hydrophobic or hydrophilic materials or a hydrophobic or hydrophilic coatings may be fluoropolymer-based.
(59) The membrane discussed herein may be formed of a number of materials. The protective housing (e.g., acoustic gap and arrangement of the electronic element and membrane) are configured to maintain acoustic performance without noticeable degradation or attenuation of the acoustic signal. The membrane 304 may be configured to protect against wind noise and/or other environmental elements, with the arrangement of the protective housing 300, 302 facilitating a higher signal-to-noise ratio along with improved sound quality. The membrane 304 may be formed of a fluoropolymer, PTFE, ePTFE membrane, nylon, silicone, polyvinylidene fluoride (PVDF) membrane, or any of combination thereof or any other similar materials. In addition, the membrane 304 may have an oleophobic treatment. For example, the membrane 304 may include a porous ePTFE membrane with oleophobic treatment in accordance with U.S. Pat. No. 5,376,441, manufactured by W. L. Gore & Associates, Inc.
(60) The invention of this application has been described above both generically and with regard to specific embodiments. It will be apparent to those skilled in the art that various modifications and variations can be made in the embodiments without departing from the scope of the disclosure. Thus, it is intended that the embodiments cover the modifications and variations of this invention provided they come within the scope of the appended claims and their equivalents.