WO2011046508A1

WO2011046508A1 - Elastomeric suspensions and integrated frame structures for electronic components

Info

Publication number: WO2011046508A1
Application number: PCT/SG2009/000383
Authority: WO
Inventors: Meng Kiang Lim; Wee Haw Koo; Beng Hai Tan
Original assignee: Siemens Medical Instruments Pte Ltd
Priority date: 2009-10-16
Filing date: 2009-10-16
Publication date: 2011-04-21

Abstract

Various embodiments include a mounting suspension (100) and integrated frame with a plurality of holes (110). In one embodiment, a mounting suspension (100) for mounting an electrical component inside a casing is provided. The mounting suspension (100) includes an elastomeric material (106) that at least partially surrounds the electrical component and has a plurality of holes (110) with a pre-determined size, a pre-determined spacing, and a pre¬ determined shape. A portion of the mounting suspension (100) is attached to the inside wall of the casing. In another embodiment, an integrated frame for mounting one or more components inside a casing is provided. The integrated frame includes a formed piece configured to match at least a portion of the casing. The formed piece includes an elastomeric material having a plurality of holes with a predetermined size, a pre-determined spacing, and a pre-determined shape and at least one cavity dimensionally configured to receive the one or more electrical components.

Description

Elastomeric Suspensions and Integrated

Frame Structures for Electronic Components

Technical Field

[0001] Various embodiments relate to an apparatus and a method to mitigating and/or elimination the transfer of mechanical and acoustic energy of an electronic component to another electronic component via an elastomeric suspension and integrated frame structure.

Background

[0002] Most hearing aids feature a small casing to contain and protect hearing aid components. Hearing aid components include, for example, receivers, microphones, SMD (surface mount technology) amplifiers, and other electronic apparatuses suitable for the operation of the hearing aid.

[0003] Technological advances in the fields of power supplies, sound processing electronics, and micro-mechanics have led to the miniaturization of hearing aid components and, consequently, the reduction of the physical size of a hearing aid. As the physical size of a hearing aid decreases, however, the difficulty of protecting and isolating acoustical and mechanical vibrations of hearing aid components increases. For example, the electronic components in a conventional hearing aid are prone to damage due to accelerative movement against the interior sides of a casing. To prevent such damage, resilient suspension has been required. Resilient suspensions have also been designed to reduce or prevent feedback oscillation of proximately located microphone and receiver components.

[0004] Conventional resilient suspensions include elastomeric rubber boots and elastomeric strips or ribbons mounted to partly or fully encircle the receiver housing and optionally include shock absorbing protrusions and several other types of resilient supports such as elastomeric rubber boots to mechanically isolate a component. Because hearing aid casing shapes and sizes may vary greatly, the effectiveness of the elastomeric rubber boots may be impaired when contact between the casing and the receiver occurs along relatively large surface areas or the rubber suspensions become wedged too tightly against a casing wall.

[0005] Various embodiments provide a receiver suspension that allows for quick and simple installation and is essentially universal for a wide range of hearing aids, including, but not limited to, Behind-The-Ear (BTE) hearing aids.

[0006] Embodiments include the use of a mounting suspension structure with a plurality of holes (i.e., a "honeycomb" structure). In one embodiment a mounting suspension for mounting an electrical component inside a casing is provided. The mounting suspension includes an elastomeric material that at least partially surrounds the electrical component and has a plurality of holes with a pre-determined size, a pre-determined spacing, and a pre-determined shape. A portion of the mounting suspension is attached to the inside wall of the casing.

[0007] In some embodiments, the suspension is attached to the inside wall of the casing by a glue. In some embodiments, the elastomeric material surrounds a top portion and a bottom portion of the electrical component. In some embodiments, the elastomeric material encircles the electrical component.

[0008] In some embodiments, the predetermined size, spacing, and shape of the plurality of holes are configured to absorb at least a minimum vibration energy. Γη some embodiments, the minimum vibration energy includes a portion of vibration energy produced by a hearing-aid receiver. In some embodiments, the minimum vibration energy may include a portion of vibration energy produced by the hearing-aid receiver that causes feedback in a microphone.

[0009] In addition to a mounting suspension, embodiments may also include the use of an integrated frame structure with a plurality of holes (i.e., a 'honeycomb' structure) and may define multiple mounting enclosures which may simplify production of a hearing aid. For example, because an integrated frame structure allows for multiple electronic components to be inserted or slotted directly into corresponding receiving spaces within the outer casing without the need to first apply an individual outer frame or resilient suspension to each component.

[0010] Assembly of the hearing aid is therefore considerably simplified because manufacture can be accomplished by inserting into an outer casing a single integrated frame structure into which the individual electronic components can be directly inserted. Or, in an alternative, the electronic components may be individually inserted into the integrated frame structure followed by insertion of the integrated frame structure into the outer casing of the hearing aid. The need for, and the manufacture and installation of, multiple outer frames or resilient suspensions, is obviated. [0011] Because the integrated frame structure is constructed from an elastomeric material, the electronic components can still be positioned within the outer casing while remaining cushioned and protected from shock caused by sudden deceleration. The single integrated frame structure, by containing multiple mounting enclosures, ensures a simple and effective solution for the problem of how to place the electronic components into the hearing aid casing in such a way that they retain their position while remaining protected from vibration and damage. In addition, because the integrated frame structure includes a plurality of holes or air pockets, it is efficient at isolating acoustic and mechanical vibrations of hearing aid components.

[0012] The integrated frame structure thereby may provide one or more of the following at least three functions: ensuring positional stability of the enclosed electronic components, ensuring that the components are cushioned, and isolating components from mechanical and acoustical vibrations of other components. The components are often connected by wires and these can be disrupted by relative movement between the components caused by shocks to the outer casing caused during routine use of the hearing aid. The cushioning provided by the single integrated frame structure to multiple components simultaneously reduces relative movement between the components and greatly reduces the possibility that electrical connection between components will be disrupted.

[0013] Additionally, the damping offered by the integrated frame structure is greater than in the conventional devices because the electronic components are no longer protected by a thin layer of rubber. They are instead supported by body of elastomeric material with a plurality of holes through which any forces of vibration or shock can be spread or dissipated through. For example, the plurality of holes provides a plurality of air pockets which impedes mechanical or acoustical energy.

[0014] The creation of multiple mounting enclosures within an elastomeric integrated frame structure may also improve positional stability within the hearing aid. Sudden decelerative shock, caused for example by dropping, may cause damage to the plastic casing of a traditionally formed hearing aid and may cause physical damage and possibly disruption to the network of internal spaces. This potentially causes permanent displacement of the inner components and may result in dislocation of their connections and therefore permanent damage to the function of the hearing aid. With use of the integrated frame structure, however, sudden decelerative shock is far less likely to cause permanent disruption to the relative position of the inner electronic components and therefore is far less likely to result in permanent damage to the function of the hearing aid.

[0015] Various embodiments provide an integrated frame that allows for quick and simple installation of electronic components into hearing aids, including, but not limited to, Behind-The-Ear (BTE) hearing aids.

[0016] In one embodiment, an integrated frame for mounting one or more electrical components inside a casing is provided. The integrated frame includes a formed piece configured to match at least a portion of the casing. The formed piece includes an elastomeric material having a plurality of holes with a pre-determined size, a predetermined spacing, and a pre-determined shape and at least one cavity dimensionally configured to receive the one or more electrical components. [0017] In some embodiments, the casing may include a hearing aid casing. In some embodiments, the predetermined size, spacing, and shape of the plurality of holes are configured to absorb at least a minimum vibration energy. In some embodiments, the at least one cavity may include at least two cavities, wherein a first cavity is dimensionally configured to receive a hearing aid receiver and a second cavity is dimensionally configured to receive a microphone. The mimmum vibration energy may include at least a vibration energy produced by the receiver that causes feedback in the microphone.

[0018] In one embodiment, a method for determining a size, a spacing, and a shape of a plurality of holes in an elastomeric material is provided. The method may include creating a model with parameters. The parameters may include a shape of at least one hole of the plurality of holes, a spacing distance between at least two holes of the plurality of holes; and, a material property of the elastomeric material. The method also may include creating a finite element model, wherein the finite model may include a vibration energy of an electronic component, running a finite element analysis, and determining if the parameters result in absorbing at least a minimum vibration energy of an electronic component.

[0019] In some embodiments, creating the model with the parameters includes creating a model of a mounting suspension with the parameters. In some embodiments, determining if the parameters result in absorbing at least the minimum vibration energy of the electronic component includes determining if the parameters result in absorbing at least a vibration energy produced by a receiver that causes feedback in a microphone. [0020] In some embodiments, creating the model with the parameters includes creating a model of an integrated frame with the parameters. In some embodiments, determining if the parameters result in absorbing at least the minimum vibration energy of the electronic component includes determining if the parameters result in absorbing at least a vibration energy produced by a receiver that causes feedback in a microphone.

Brief Description of the Drawings

[0021] In the drawings, like reference characters generally refer to the same parts throughout the different views. The drawings are not necessarily to scale, emphasis instead generally being placed upon illustrating the principles of the embodiments. In the following description, various embodiments are described with reference to the following drawings, in which:

[0022] FIG. 1 shows a vertical cross-section of a suspension embodiment;

[0023] FIG. 2 shows vertical cross-section of an integrated frame embodiment;

[0024] FIG. 3 shows a perspective view of an integrated frame embodiment;

[0025] FIG. 4 shows an exploded view of an integrated frame embodiment; and

[0026] FIG. 5 shows method steps of an embodiment for determining a hole size, hole shape, and/or hole spacing for a suspension or integrated frame structure. Description

[0027] The following detailed description refers to the accompanying drawings that show, by way of illustration, specific details and embodiments. These embodiments are described in sufficient detail to enable those skilled in the art to practice the

embodiments. Other embodiments may be utilized and structural, logical, and electrical changes may be made without departing from the scope of the embodiments. The various embodiments are not necessarily mutually exclusive, as some embodiments can be combined with one or more other embodiments to form new embodiments.

[0028] Embodiments relate to mitigating and/or elimination the transfer of mechanical and acoustic energy of an electronic component to another electronic component. The terms "vibration energy" and vibrational energy" encompass both meachanical and acoutic enegry. Although the below disclosed embodiments are directed to hearing aids, alternative embodiments may be included in other electronic devices where mitigating and/or elimination the transfer of mechanical and acoustic energy of a electronic component is a concern.

[0029] FIG. 1 shows a vertical cross-section of a suspension embodiment. Suspension apparatus 100 includes transducer 102, transducer termination 104, transducer tubing 106, elastomeric material 108, holes 110, and surface 112. Elastomeric material 108 include, but is not limited to, natural rubber, synthetic rubber, and thermoplastic elastomers. In some embodiments, the elastomeric material 108 is made of silicone rubber.

[0030] Elastomeric material 108 comprises a plurality of holes 110. If transducer 102 vibrates, each of the holes 110 absorbs some portion of the vibration energy. The size, number, and shape of holes 110 and type and thickness of elastomeric material 108 determines the amount of vibration energy suspension apparatus 100 may absorb.

Depending on design goals, suspension apparatus 100 may be tuned, for example, to absorb a percentage of a maximum transducer vibration energy. Suspension apparatus 100 may also be tuned to absorb a particular bandwidth of a transducer's vibrational energy. A method to design a suspension apparatus 100 with a specific absorption potential is more fully explained in FIG. 5, below.

[0031] Γη some embodiments, holes 110 are uniform in shape and size. In some embodiments, holes 110 are non-uniform in shape and/or size. The geometry of holes 110 may be defined by as a circle, square, hexagon, or any other polygon. In some embodiments, holes 110 extend completely through suspension apparatus 100. In some embodiments, holes 110 extend through a portion of suspension apparatus 100.

[0032] Suspension apparatus 100 may be attached to a hearing aid casing (not shown) by means of glue applied to the casing and/or surface 112. In some embodiments, surface 112 may be smooth. Similarly, elastomeric material 108 may be attached to transducer 102 by means of glue. In some embodiments, elastomeric material 108 may form a cavity in which transducer 102 (or another hearing aid component) snugly fits into. In some embodiments, transducer tubing 106 supports transducer 102 and elastomeric material 108.

[0033] In some embodiments, elastomeric material 108 may be attached to the top and bottom of transducer 102, thereby sandwiching transducer 102 between a top layer and bottom layer of elastomeric material 108. [0034] Transducer tubing 106 typically guides sounds produced by the transducer towards a user's ear or guides sounds from outside the hearing aid towards a hearing aid transducer.

[0035] It will be understood that suspension apparatus 100 shown in FIG. 1 is only one possible configuration and that there may be many variations or additions within the scope of the invention. For example, transducer 102 may be any type of electronic component where vibration isolation and/or shock protection is desired.

[0036] FIG. 2 shows a vertical cross-section of an integrated frame embodiment. Formed piece 202 may be formed out of an elastomeric material or any other resilient material with similar dampening properties. Formed piece 202 may be of similar shape and size of a hearing aid casing such that the outer walls of formed piece 202 fits snugly with the inner walls of a hearing aid casing. Formed piece may include a plurality of holes 204. Mounting enclosures 206, 208, 210, and 212 may be sunk into the surface of formed piece 202 and may be shaped to accommodate suitable electronic components intended for the hearing aid. In this implementation, mounting enclosure 206 may be shaped to accommodate an amplifier (not shown), mounting enclosure 208 may accommodate receiver 214 and mounting enclosures 210 and 212 accommodate microphones 216 and 218, respectively. Mounting enclosures may be of any shape suitable to accommodate the intended corresponding component.

[0037] Each hole of the plurality of holes 204 may act as an absorber for vibrations produced, for example, by receiver 214. Thus, the vibration energy may be reduced as it propagates through formed piece 202 to prevent feedback oscillation and other mechanical-acoustical problems. In comparison to conventional hearing aids, hearing aid components may be placed closer together and still avoid feedback oscillation.

Moreover, receiver 214 may perform at gain levels in formed piece 202 that would cause feedback oscillation with microphones 216 and 218 if a conventional elastomeric suspension were used.

[0038] It will be understood that formed piece 202 shown in FIG. 2 is only one possible configuration and that there may be many variations or additions within the scope of the invention. For example, holes 204 may be located in only a portion of formed piece 202 where vibration isolation may be desired, e.g., only in the area around receiver 214 and microphones 216 and 218. In some embodiments, formed piece 202 may take on only a portion of a hearing aid shell and, for example, house only receiver 214 and microphones 216 and 2 IS. In some embodiments, mounting enclosures may also include protrusions in any suitable shape to support electronic component.

[0039] FIG. 3 shows a perspective view of an integrated frame embodiment. Formed piece 302, includes mounting enclosures 304, 306, 308, and 310 into which various components, for example microphones, a receiver, or a SMD (surface mount technology), or combinations thereof, may be placed. Formed piece 302 also includes groove 312 for a wire to connect components housed in mounting enclosures 304 and 306

[0040] FIG. 4 shows an exploded view of an integrated frame embodiment. Outer housing piece 402 is a typical part of a BTE hearing aid case. Electrical components to be included in the hearing aid, for example receiver 404, SMD amplifier 408,

microphones 410, are placed or inserted into the corresponding mounting enclosures of the formed piece 412. Outer housing piece 412 is a typical part of a BTE hearing aid case, which, along with outer housing piece 402, snaps together to enclose formed piece 412 and receiver 404, SMD amplifier 408, microphones 410.

[0041] FIG. 5 shows method steps of an embodiment for determining a hole size, hole shape, and/or hole spacing for a suspension or integrated frame structure.

[0042] At 502, a three-dimensional model of the honeycomb structure is created. The honeycomb structure may be a mounting suspension or an integrated frame.

[0043] At 504, parameters of the honeycomb structure are chosen. Parameters may include a hole shape, a spacing between the holes, the size of a hole (e.g., cross section area, circumference, and/or volume) and material properties of the honeycomb structure such as a Shore hardness number.

[0044] At 506, a finite element model is created. Creating a finite element model may include defining geometry, nodes, elements, specifying material properties of elements, loading conditions, and boundary conditions. For example, defining geometry may include defining geometric nonlinearities due to finite strains of elements of the finite element model. Another example includes defining the thickness of an element, such as a homogeneous shell, e.g., outer housing pieces 402 and 412 of FIG. 4. Creating a finite element model may also include defining a vibration energy produced by a hearing-aid receiver.

[0045] At 508, a finite element program performs an analysis, wherein an equation is formulated that includes the above parameters, and the equation is solved. At 510, the finite elements program reports results, which may include node and element values. These values may include, for example, magnitude of the honeycomb structure displacement caused by a vibrating receiver, as well as stresses and reaction forces.

Values may also include a vibration energy produced by the hearing-aid receiver that causes feedback in the microphone.

[0046] At 512, finite element program posts the process results. Process results may include plots and code checks.

[0047] At 514, user may vary the parameters of hole shape, spacing between the holes, and material properties of the honeycomb structure to observe the degree of dampening caused by the honeycomb structure over various vibration amplitudes and frequencies. The method may then repeat at 506. Once the honeycomb structure exhibits the dampening properties desired, a physical model may be created for further testing or for use in a product. Depending on design goals, the desired dampening properties may include a honeycomb structure configured to dampen a broad range vibration energy or dampen only the vibration energy of a hearing aid receiver that causes feedback in a hearing aid microphone.

[0048] While embodiments have been particularly shown and described, it should be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. The scope of the invention is thus indicated by the appended claims and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced.

Claims

CLAIMS WHAT IS CLAIMED IS:

1. A mounting suspension for mounting an electrical component inside a casing, the mounting suspension comprising an elastomeric material, the elastomeric material at least partially surrounding the electrical component and having a plurality of holes with a predetermined size, a pre-determined spacing, and a pre-determined shape, wherein a portion of the mounting suspension is attached to the inside wall of the casing.

2. The suspension of claim 1, wherein the portion of the mounting suspension is attached to the inside wall of the casing by a glue.

3. The suspension of claim 1, wherein the elastomeric material surrounds a top portion and a bottom portion of the electrical component.

4. The suspension of claim 1, wherein the elastomeric material encircles the electrical component.

5. The suspension of claim 1, wherein the predetermined size, spacing, and shape of the plurality of holes are configured to absorb at least a minimum vibration energy.

6. The suspension of claim 5, wherein the minimum vibration energy comprises a portion of vibration energy produced by a hearing-aid receiver.

7. The suspension of claim 6, wherein the niinimum vibration energy comprises a portion of vibration energy produced by the hearing-aid receiver that causes feedback in a microphone.

8. An integrated frame for mounting one or more electrical components inside a casing, the integrated frame comprising:

a formed piece configured to match at least a portion of the casing, the formed piece comprising:

an elastomeric material having a plurality of holes with a pre-determined size, a pre-determined spacing, and a pre-determined shape; and

at least one cavity dimensionally configured to receive the one or more electrical components.

9. The integrated frame of claim 8, wherein the casing comprised a hearing aid casing.

10. The suspension of claim 9, wherein the predetermined size, spacing, and shape of the plurality of holes are configured to absorb at least a minimum vibration energy.

11. The suspension of claim 10, wherein the at least one cavity comprises at least two cavities, wherein a first cavity is dimensionally configured to receive a hearing aid receiver and a second cavity is dimensionally configure to receive a microphone, wherein the minimum vibration energy comprises at least a vibration energy produced by the receiver that causes feedback in the microphone.

12. A method for determining a size, a spacing, and a shape of a plurality of holes in an elastomeric material, the method comprising:

using a processor to perform at least a portion of one or more of the following steps: creating a model of the elastomeric material with parameters, the parameters comprising:

a shape of at least one hole of the plurality of holes;

a spacing distance between at least two holes of the plurality of holes; and a material property of the elastomeric material;

creating a finite element model, the finite model including a vibration energy of an electronic component;

rurining a finite element analysis; and

determining if the parameters result in absorbing at least a minimum vibration energy of the electronic component.

13. The method of claim 12, wherein creating the model of the elastomeric material with the parameters comprises creating a model of a mounting suspension with the parameters.

14. The method of claim 13, wherein determining if the parameters result in absorbing at least the minimum vibration energy of the electronic component comprises determining if the parameters result in absorbing at least a vibration energy produced by a receiver that causes feedback in a microphone.

15. The method of claim 12, wherein creating the model of the elastomeric material with the parameters comprises creating a model of an integrated frame with the parameters.

16. The method of claim 15, wherein determining if the parameters result in absorbing at least the minimum vibration energy of the electronic component comprises determining if the parameters result in absorbing at least a vibration energy produced by a receiver that causes feedback in a microphone.