WO2017157496A1

WO2017157496A1 - Electroacoustic transducer with improved frame construction

Info

Publication number: WO2017157496A1
Application number: PCT/EP2016/081513
Authority: WO
Inventors: Erich Klein; Michael SCHÖFFMANN
Original assignee: Sound Solutions Austria Gmbh
Priority date: 2016-03-17
Filing date: 2016-12-16
Publication date: 2017-09-21
Also published as: CN108886666B; TWI736568B; CN108886666A; TW201735663A

Abstract

A new audio transducer for mobile devices, in particular for a micro speaker, having a pot plate (180), a collar (116), a membrane (112), a magnet system (152, 160) and a coil assembly (130). The magnet system (152, 160) may optionally comprise a ring plate (158) affixed to a population of outer magnets (154). Said collar (116) is directly mounted to said ring plate (158) and/or to said pot plate (180).

Description

ELECTRO ACOUSTIC TRANSDUCER WITH IMPROVED FRAME CONSTRUCTION

BACKGROUND OF THE INVENTION a. Field of the Invention

[0001] The invention relates to an audio transducer, such as a speaker or a receiver to transduce an electrical audio signal into acoustic sound. This invention furthermore relates to a micro speaker optimized for high acoustic output and located within a small volume of a mobile device, such as a mobile phone, a tablet, a gaming device, a notebook or similar device. b. Background Art

[0002] Prior art micro speakers for use in mobile devices include a coil fixed to the membrane of the speaker. The coil includes two leads to feed an electrical signal into the coil. The coil is arranged within a magnetic field formed of a population of magnets. The electrical signal fed into the coil causes the coil and connected membrane to vibrate which generates an acoustic sound in relation to the electrical signal. Prior art micro speakers include a plastic frame to align and fix the parts of the speaker. The frame includes contact pads which provide the electrical interface between the coil and the audio electronics of the mobile device.

[0003] A particular drawback of the speaker of the kind above is the connection between the plastic frame and metal parts of the speaker. Generally, gluing different materials (here metal to plastic) causes problems. In particular, applying the right amount of glue to the right place is not easy at the high speeds necessary in mass production. Moreover, such a connection usually suffers from comparably low adhesive forces. In addition, different thermal expansion of the parts may induce stress into the membrane, which leads to poor audio performance. In the long term, the connection may even break. In this context, one should note that especially mobile devices are often exposed to extreme temperatures, ranging from about -20°C to +50°C.

SUMMARY OF THE INVENTION [0004] It is an object of the invention to have an audio transducer for mobile devices without the disadvantages of known transducers. A new audio transducer for mobile devices, in particular for a micro speaker, comprises a pot plate, a collar, a membrane, a magnet system and a coil assembly. The collar comprises a first portion substantially parallel to the pot plate, a hole extending through the first portion of the collar, and a second portion extending substantially perpendicular downward from the first portion. A perimeter of the membrane is affixed to the first portion of the collar. The magnet system comprises a perimeter magnet assembly with a population of outer magnets arranged proximate a perimeter of the pot plate, and/or a center magnet assembly with a center magnet affixed to the pot plate and substantially surrounded by the population of outer magnets of the perimeter magnet system, and an air gap formed in the magnetic system. The center magnet assembly may also comprise a top plate affixed to the center magnet. The coil assembly finally comprises a coil located in the air gap, wherein the coil has a top side affixed to the membrane, and a pair of electrical leads extending from the coil.

[0005] In a first case A), said collar is directly mounted to said pot plate. In an alternative second case B), said perimeter magnet assembly comprises a ring plate affixed to the population of outer magnets, and said collar is directly mounted to said ring plate. In yet another alternative third case C), said perimeter magnet assembly comprises a ring plate affixed to the popu- lation of outer magnets, and said collar is directly mounted to said ring plate and to said pot plate.

[0006] Advantages of this new speaker are the reduced number of parts and an eased manufacturing of the same. Especially, if the collar and at least one of the pot plate and the ring plate are made of metal, the collar can be welded to the pot plate and/or the ring plate. In this way, a quite stable arrangement is obtained. For example, side tabs of the collar are used for connecting the collar to the ring plate and/or the pot plate. Welding can be done especially by means of laser welding. However, other welding methods are applicable as well, for example ultrasonic welding.

[0007] A particular advantage of the proposed speaker furthermore is the avoidance of the plastic frame and thus the avoidance of a connection between a plastic frame and metal parts of the speaker. Connecting materials of the same kind (here especially metal parts) usually is comparably easy. There is no different thermal expansion of the parts, which could induce stress into the membrane. Accordingly, the speaker benefits from good audio performance. Furthermore, the connection is stable even in the long term. Problems with gluing (e.g. difficult appliance of glue at high speeds) can be avoided if the parts are welded.

[0008] The membrane may be attached to collar before mounting the same to ring plate / pot plate or afterwards. If membrane is attached to collar before welding the same to the ring plate / pot plate, laser welding may avoid extensive heating of the membrane. Further details and advantages of an audio transducer of the disclosed kind will become apparent in the following description and the accompanying drawings.

[0009] In a preferred embodiment, the collar comprises a support tab extending substantially perpendicular outward from the second portion, and the coil assembly comprises a flexible printed circuit having a pair of contact pads. Each electrical lead is electrically connected to a respective contact pad, and the support tab of the collar is affixed to the flexible printed circuit. An advantage of this new speaker is the reduced number of electrical connections between the leads of the coil and the driver of the coil. This helps to reduce the number and size of the parts of the micro speaker and aids in increasing sound quality and durability of the speaker.

[0010] While embodiments of the audio transducer are shown and described as having a rectangular shape, it will be understood that in other embodiments, the audio transducer may have a variety of shapes, including, but not limited to, circular and ovular. Accordingly, the invention is not limited to audio transducers having a rectangular shape.

BRIEF DESCRIPTION OF THE DRAWINGS

[0011] These and other aspects, features, details, utilities, and advantages of the invention will become more fully apparent from the following detailed description, appended claims, and accompanying drawings, wherein the drawings illustrate features in accordance with exemplary embodiments of the invention, and wherein: [0012] Figure 1 shows an exploded top perspective view of the relevant parts of a prior art rectangular micro speaker;

[0013] Figure 2 A shows a bottom perspective view of the relevant parts of a prior art rectan- gular micro speaker;

[0014] Figure 2B shows a bottom perspective view of the relevant parts of a prior art rectangular micro speaker; [0015] Figure 3 shows an exploded top perspective view of a rectangular micro speaker according to a first embodiment of the invention;

[0016] Figure 4 shows a top perspective view of a coil assembly of a rectangular micro speaker according to the first embodiment of the invention;

[0017] Figure 5 shows a top perspective view of a rectangular micro speaker according to the first embodiment of the invention;

[0018] Figure 6 is a flowchart describing a method of manufacturing the rectangular micro speaker according to the first embodiment of the invention;

[0019] Figure 7 is a top perspective view of a rectangular micro speaker within an enclosure according to the first embodiment of the invention; [0020] Figure 8A is a top perspective view of a collar of a rectangular micro speaker according to a second embodiment of the invention;

[0021] Figure 8B is a bottom perspective view of a rectangular micro speaker according to a second embodiment of the invention;

[0022] Figure 9A is a bottom perspective view of a collar of a rectangular micro speaker according to the third embodiment of the invention; [0023] Figure 9B is a top perspective view of a collar of a rectangular micro speaker according to the third embodiment of the invention.

[0024] Like reference numbers refer to like or equivalent parts in the several views.

DETAILED DESCRIPTION OF EMBODIMENTS

[0025] Various embodiments are described herein to various apparatuses. Numerous specific details are set forth to provide a thorough understanding of the overall structure, function, manufacture, and use of the embodiments as described in the specification and illustrated in the accompanying drawings. It will be understood by those skilled in the art, however, that the embodiments may be practiced without such specific details. In other instances, well-known operations, components, and elements have not been described in detail so as not to obscure the embodiments described in the specification. Those of ordinary skill in the art will under- stand that the embodiments described and illustrated herein are non- limiting examples, and thus it can be appreciated that the specific structural and functional details disclosed herein may be representative and do not necessarily limit the scope of the embodiments, the scope of which is defined solely by the appended claims. [0026] Reference throughout the specification to "various embodiments," "some embodiments," "one embodiment," or "an embodiment," or the like, means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Thus, appearances of the phrases "in various embodiments," "in some embodiments," "in one embodiment," or "in an embodiment," or the like, in places throughout the specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. Thus, the particular features, structures, or characteristics illustrated or described in connection with one embodiment may be combined, in whole or in part, with the features, structures, or characteristics of one or more other embodiments without lim- itation given that such combination is not illogical or non-functional. [0027] It must be noted that, as used in this specification and the appended claims, the singular forms "a," "an" and "the" include plural referents unless the content clearly dictates otherwise. [0028] The terms "first," "second," and the like in the description and in the claims, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the invention described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "include," "have," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements is not necessarily limited to those elements, but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

[0029] All directional references (e.g., "plus", "minus", "upper", "lower", "upward", "downward", "left", "right", "leftward", "rightward", "front", "rear", "top", "bottom", "over", "under", "above", "below", "vertical", "horizontal"," clockwise", and "counterclockwise") are only used for identification purposes to aid the reader's understanding of the present disclo- sure, and do not create limitations, particularly as to the position, orientation, or use of the any aspect of the disclosure. It is to be understood that the terms so used are interchangeable under appropriate circumstances such that the embodiments of the invention described herein are, for example, capable of operation in other orientations than those illustrated or otherwise described herein.

[0030] As used herein, the phrased "configured to," "configured for," and similar phrases indicate that the subject device, apparatus, or system is designed and/or constructed (e.g., through appropriate hardware, software, and/or components) to fulfill one or more specific object purposes, not that the subject device, apparatus, or system is merely capable of per- forming the object purpose.

[0031] Joinder references (e.g., "attached", "coupled", "connected", and the like) are to be construed broadly and may include intermediate members between a connection of elements and relative movement between elements. As such, joinder references do not necessarily infer that two elements are directly connected and in fixed relation to each other. It is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative only and not limiting. Changes in detail or structure may be made without departing from the spirit of the invention as defined in the appended claims.

[0032] All numbers expressing measurements and so forth used in the specification and claims are to be understood as being modified in all instances by the term "about." [0033] Figure 1 shows an exploded perspective view of the relevant parts of a prior art rectangular micro speaker 10. Speaker 10 comprises a membrane 12 that is typically built out of one or more layers of material, such as, for example, Ethere Ketone (PEEK), Acrylate and/or Thermoplastic Elastomeric (TEP), Polyetherimide (PEI), and/or other materials known in the art. Membrane 12 may also include a membrane plate 14 to stiffen membrane 12. Speaker 10 furthermore comprises a coil 32 with leads 34. An electrical signal to drive coil 32 is fed into coil 32 through leads 34. Coil 32 of assembled speaker 10 is fixed to membrane 12 with an adhesive, such as, for example, glue, tape, or other adhesives known in the art.

[0034] Speaker 10 includes a magnet system 50 comprising a perimeter magnet assembly 52 and a center magnet assembly 60. Perimeter magnet assembly 52 includes four magnets 54 arranged on the rectangular sides of the rectangular speaker 10 and ring plate 58 fixed to magnets 54. Center magnet assembly 60 includes magnet 62 arranged in the center of speaker 10 and top plate 64 fixed to magnet 62. Perimeter magnet assembly 52, center magnet assembly 60, and pot plate 80 affixed to perimeter and center magnet assemblies 52, 60 opposite ring and top plates 58, 64 form magnetic field guide 68. Magnetic field guide 68 guides and focuses the magnetic field of magnets 54 and 62 in an air gap 70 between perimeter magnet assembly 52 and center magnet assembly 60, into which coil 32 is arranged in the assembled speaker 10. [0035] Prior art micro speaker 10 further includes frame 90 to assemble and align membrane 12 with magnet system 50. Coil 32 fits into air gap 70 and is able to translate up and down within air gap 70 according to the electrical signal fed into coil 32 through leads 34. Frame 90 typically is made from a molded plastic which enables frame 90 to have a complex surface with openings which permit airflow and fixation of other parts of speaker 10. The ends of leads 34 of coil 32 are soldered to contact pads 92t, that are fixed in to top side of frame 90 during an assembly process. As shown in FIG. 2A, the bottom side of frame 90 includes contact pads 92b which are electrically connected with contact pads 92t on the top side of frame 90. As shown in FIG. 2B, a further electrical connection is made with flexible printed circuit 94 which includes contact pads 96. Contact pads 96 of flexible printed circuit 94 are soldered to contact pads 92b during an assembly process. The electrical signal to drive coil 32 is fed through flexible printed circuit 94, contact pads 96, contact pads 92b, contact pads 92t, and into leads 34. Furthermore as shown in FIGS. 2A and 2B, pot plate 80 includes bottom vents 98 which permit airflow between a back volume (not shown) and the back volume side of the membrane 12. Bottom vents 98 permit an undistorted vibration of membrane 12 according to the electrical signal fed into coil 32.

[0036] The relevant parts of a first embodiment of the invention are shown in FIGS. 3, 4, 5, and 7. Figure 3 shows an exploded perspective view of the relevant parts of a rectangular speaker 110. Figure 4 shows a perspective view of an assembly of a coil 132 and flexible printed circuit 136. Figure 5 shows a top perspective view of the relevant parts of the assembled speaker 110. Figure 6 is a flowchart describing a method of manufacturing speaker 110. Figure 7 is a top perspective view of the assembled speaker 110 within an enclosure 190.

[0037] Speaker 110 comprises a membrane 112, a collar 116, a coil assembly 130, a magnet system 150, and a pot plate 180. Membrane 112 may be built out of one or more layers of material, such as, for example, Ethere Ketone (PEEK), Acrylate and/or Thermoplastic Elasto- meric (TEP), Polyetherimide (PEI), and/or other materials known in the art. Membrane 112 may also include a membrane plate 114 to stiffen membrane 112.

[0038] Speaker 110 includes a magnet system 150 comprising a perimeter magnet assembly 152 and a center magnet assembly 160. Perimeter magnet assembly 152 includes four magnets 154 arranged on the rectangular sides of the rectangular speaker 110 and ring plate 158 fixed to magnets 154. Center magnet assembly 160 includes magnet 162 arranged in the center of speaker 110 and top plate 164 fixed to magnet 162. Perimeter magnet assembly 152, center magnet assembly 160, and pot plate 180 affixed to perimeter and center magnet assemblies 152, 160 opposite ring and top plates 158, 164 form magnetic field guide 168. Magnetic field guide 168 guides and focuses the magnetic field of magnets 154 and 162 in an air gap 170 between perimeter magnet assembly 152 and center magnet assembly 160, into which coil 132 is arranged in the assembled speaker 1 10. [0039] Speaker 1 10 includes coil assembly 130 having coil 132, leads 134, and flexible printed circuit 136. An electrical signal to drive coil 132 is fed into coil 132 through flexible printed circuit 136 and leads 134. Coil 132 of assembled speaker 1 10 is fixed to membrane 1 12 with an adhesive, such as, for example, glue, tape, or other adhesives known in the art. Optionally, leads 134 of coil 132 may directly be connected to flexible printed circuit 136 as shown in the Figures. In this case, flexible printed circuit 136 includes a pair of contact pads 138 on a first terminal end of flexible printed circuit 136, which are in electrical communication with contact pads 140 on a second terminal end of the printed circuit 136 opposite the first. The electrical communication between contact pads 140 and 138 may be accomplished using traces and/or vias as is known in the art. Leads 134 are electrically connected by a sol- der connection to contact pads 138 to permit an electrical signal to flow from a source (not shown) into contact pads 140, through traces and/or vias in flexible printed circuit 136, through contact pads 138, through leads 134 and into coil 132. It will be understood by those in the art, that in various embodiments, the electrical connection between leads 134 and flexible printed circuit 136 may be accomplished in a variety of ways known in the art, for exam- pie, by inserting leads 134 into an electrical connector affixed to flexible printed circuit 136. Electrical connection of the coil 132 may also be accomplished as shown in FIGS. 1 to 2B.

[0040] According to the invention, the frame 90 of prior art micro speaker 10 is replaced with collar 1 16 as shown in FIG. 3. Collar 1 16 has a first portion 1 18 that is substantially horizon- tal and substantially parallel with pot plate 180. A substantially rectangular opening 120 is provided in first portion 1 18 through which coil 132 may translate during operation of speaker 1 10. First portion 1 18 serves as a rim to which the perimeter of membrane 1 12 is affixed typically, for example, by glue or adhesive. Extending downward and substantially perpendicular from the sides of first portion 1 18 of collar 1 16 is a second portion, shown as side tabs 122. Preferably, collar 1 16 includes four (4) side tabs; however, it will be understood that, in various embodiments, for example, collar 1 16 may include from about two (2) tabs to about four (4) tabs (e.g., two (2) tabs, three (3) tabs, four (4) tabs). In other embodiments, collar 1 16 may include less than two (2) tabs. In yet other embodiments, collar 1 16 may include more than four (4) tabs.

[0041] With continued reference to FIG. 3, collar 1 16 further includes optional openings 124 proximate the corners of collar 1 16 between tabs 122. Preferably, collar 1 16 includes four (4) openings; however, it will be understood that, in various embodiments, for example, collar 1 16 may include from about two (2) openings to about four (4) openings (e.g. , two (2) openings, three (3) openings, four (4) openings). In other embodiments, collar 1 16 may include less than two (2) openings. In yet other embodiments, collar 1 16 may include more than four (4) openings.

[0042] Openings 124 serve as side vents, which permit airflow between a back volume (not shown) and the back volume side of membrane 1 12. As illustrated in FIGS. 3 and 5, openings 124 are substantially aligned with the gaps 156 between magnets 154 of magnet system 150 and thus speaker 1 10 includes a substantially clear air pathway between the back volume and the back volume side of membrane 1 12. Therefore, openings 124 permit an undistorted vibration of membrane 1 12 in response to the electrical signal fed into coil 132. With the inclusion of openings 124 on collar 1 16, back vents are not required in pot plate 180. By not requiring back vents on pot plate 180, the geometry and/or features of pot plate 180 can be simplified as compared to pot plate 80 of prior art speakers, thus reducing component cost. It will be understood however, that in various embodiments, in addition to or alternative to openings on collar 1 16, back vents may be provided on pot plate 180.

[0043] Preferably, collar 1 16 further includes a stabilizing tab 126 extending substantially horizontally from right tab 122. As shown in FIG. 5, stabilizing tab 126 interfaces with flexible printed circuit 136, serves to stabilize flexible printed circuit 136, provides protection between the electrical connection between leads 134 and contact pads 138, and maintains the positions of collar 1 16 and coil assembly 130 in speaker 1 10. Stabilizing tab 126 is affixed to flexible printed circuit 136 using an adhesive 142 (see FIG. 3), such as, for example, glue, tape, or other adhesives known in the art.

[0044] According to a first embodiment of the invention, collar 1 16 is directly mounted to the pot plate 180, for example glued onto the pot plate 180 (case A). For example, side tabs 122 are used for connecting the collar 116 to the pot plate 180. In an advantageous embodiment, collar 116 and pot plate 180 are made of metal, preferably of steel. In yet another advantageous embodiment, collar 116 is welded to pot plate 180, especially by means of laser welding. However, other welding methods are applicable as well, for example ultrasonic welding.

[0045] According to a further embodiment of the invention, collar 116 is directly mounted onto ring plate 158, for example glued onto ring plate 158 (case B). In an advantageous embodiment, collar 116 and ring plate 158 are made of metal, preferably of steel. In yet another advantageous embodiment, collar 116 is welded onto ring plate 158, especially by means of laser welding. However, other welding methods are applicable as well, for example ultrasonic welding.

[0046] According to yet another embodiment of the invention, collar 116 is directly mounted onto ring plate 158 and to pot plate 180, for example glued to ring plate 158 and pot plate 180. In an advantageous embodiment, collar 116, pot plate 180 and ring plate 158 are made of metal, preferably of steel. In yet another advantageous embodiment, collar 116 is welded to the ring plate 158 and to the pot plate 180, especially by means of laser welding. However, other welding methods are applicable as well, for example ultrasonic welding. If collar 116 is mounted both to the ring plate 158 and the pot plate 180 a quite stable arrangement is ob- tained. For example, side tabs 122 are used for connecting the collar 116 to the ring plate 158 and the pot plate 180.

[0047] Membrane 112 may be attached to collar 116 before mounting the same onto ring plate 158 / pot plate 180 or afterwards. If membrane 112 is attached to collar 116 before welding the same onto ring plate 158 / pot plate 180, laser welding may avoid extensive heating of the membrane 112. However, laser welding can also be used if membrane 112 is attached to collar 116 after welding.

[0048] Unlike prior art micro speaker 10 shown in FIGS. 1, 2A, and 2B, micro speaker 110 does not require frame 90. In an advantageous embodiment micro speaker 110 furthermore does not require contact pads 92t and contact pads 92b. By eliminating the additional components required to transmit the electrical signal from the source to coil 132, the size may be reduced, the component and manufacturing costs may be reduced, and durability and sound quality may be increased for speaker 110 as compared to prior art speaker 10. For example, by connecting leads 134 directly to contact pads 138 of flexible printed circuit 136, the number of electrical connections are reduced to one for each lead 134. [0049] As shown in FIGS. 3 and 4, leads 134 of coil 132 extend from the side of coil 132 proximate flexible printed circuit 136 and each lead 134 forms a short loop. This allows leads 134 to be shorter in length than leads 34 of prior art micro speaker 10. However, in other embodiments, for example, leads 134 of coil 132 may extend from the side of coil 132 distal flexible printed circuit 136 and loop inward to be electrically connected to contact pads 138 of flexible printed circuit 136. As shown, leads 134 extend from the bottom of coil 132 and may be substantially horizontal and substantially in-plane with flexible printed circuit 136 when coil is in the rest position. In various embodiments, speaker 110 may also include one or more of the support members for supporting coil 132 and/or leads 134 as described in U.S. Provisional Application Serial No. 62/147,801, filed on April 15, 2015, entitled "Speaker with Sup- ported Coil Wire," the entire disclosure of which is incorporated by reference herein.

[0050] The assembled speaker 110 is shown in FIG. 5. Now with reference to FIG. 6, an embodiment of assembling speaker 110 is illustrated. At step 600, leads 134 of coil 132 are soldered to contact pads 138 of flexible printed circuit 136 to form coil assembly 130. At step 602, coil assembly 130 is placed inside perimeter magnet assembly 152, with leads 134 looping around the right magnet 154 of perimeter magnet assembly 152. At step 604, collar 116 is placed on top of and around perimeter magnet assembly 152 and support tab 126 of collar 116 is affixed to flexible printed circuit 136 of coil assembly 130. At step 606, pot plate 180 with center magnet assembly 160 is affixed to magnets 154 of perimeter magnet assembly 152 on opposite side of ring plate 158. At step 608 perimeter of membrane 112 is affixed to collar 116, collar 116 is affixed to ring plate 158 and pot plate 180 and coil 132 is affixed to membrane 112. This method results in assembled speaker 110 as shown in FIG. 5. Instead of using both the center magnet and the perimeter magnet assembly, only the center magnet or the perimeter magnet assembly can be used as well.

[0051] While various steps are described herein in one order, it will be understood that other embodiments of the method can be carried out in any order and/or without all of the described steps without departing from the scope of the invention. Particularly, membrane 112 may be attached to collar 116 before mounting (welding) the same to pot plate 180 / ring plate 158. Furthermore, it should be noted that collar 116 may be affixed to pot plate 180 or ring plate 158 only. Moreover, ring plate 158 is not a mandatory part of speaker 110 as mentioned before and may be omitted.

[0052] Assembled speaker 110, may be installed in an enclosure 190 as shown in FIG. 7. Enclosure 190 is illustrated with a sound path terminating in a side firing port 192; however, it will be understood that in various embodiments, the enclosure of speaker 110 may include a sound path terminating in a top or bottom firing port. Enclosure 190 further includes a pas- sageway through which flexible printed circuit 136 exits so that it may be connected to circuitry source (not shown) for driving speaker 110.

[0053] Another embodiment of speaker 210 of the invention is illustrated in FIGS. 8 A, 8B and are described below. Some features of one or more of speakers 110 and 210 are common to one another and, accordingly, descriptions of such features in one embodiment should be understood to apply to other embodiments. Furthermore, particular characteristics and aspects of one embodiment may be used in combination with, or instead of, particular characteristics and aspects of another embodiment. [0054] With reference to FIG. 8 A, a portion of speaker 210 is shown. Speaker 210 comprises a membrane 112, a collar 216, a coil assembly 130, a magnet system 150, and a pot plate 180. Speaker 210 is substantially the same as speaker 110 except for the design of collar 216. collar 216 has a first portion 218 that is substantially horizontal and substantially parallel with pot plate 180 (see FIG. 8B). A substantially rectangular opening 220 is provided in first por- tion 218 through which coil 132 may translate during operation of speaker 210. First portion 218 serves as a rim to which the perimeter of membrane 112 is affixed typically, for example, by glue or adhesive. Extending downward and substantially perpendicular from the sides of first portion 218 of collar 216 is a second portion, shown as sidewall 222. Sidewall 222 extends around the perimeter of collar 216.

[0055] With continued reference to FIG. 8A, sidewall 222 includes a population of openings 224 extending through sidewall 222 proximate the corners of collar 216. Openings 224 are shown as substantially circular holes arranged in rows and columns. In various embodiments, for example, openings 224 may be laser cut into sidewall 222. Openings 224 serve as side vents which permit airflow between a back volume (not shown) and the back volume side of membrane 112. As illustrated in FIG. 8A, openings 224 are substantially aligned with the gaps between magnets 154 of magnet system 150 and thus speaker 210 includes a substan- tially clear air pathway between the back volume and the back volume side of membrane 112. Therefore, openings 224 permit an undistorted vibration of membrane 112 in response to the electrical signal fed into coil 132. With the inclusion of openings 224 on collar 216, back vents are not required in pot plate 180 as shown in FIG. 8B. By not requiring back vents on pot plate 180, the geometry and/or features of pot plate 180 can be simplified as compared to pot plate 80 of prior art speakers, thus reducing component cost. It will be understood however, that in various embodiments, in addition to or alternative to openings on collar 216, back vents may be provided on pot plate 180.

[0056] It will be understood that the number and/or the size of openings 224 may be altered to provide the appropriate side venting to a back volume (not shown) to achieve the desired acoustic performance for speaker 210. Furthermore, as described in U.S. Provisional Application Serial No. 62/237,961, filed on October 6, 2015, entitled "Electroacoustic Transducer," the entirety of which is incorporated by reference, openings 224 may have a maximum dimension smaller than an adsorber material filled into an enclosure. The adsorber material may be, for example, the zeolite material described in U.S. Published Patent Application

2013/0170687, published on July 4, 2013, entitled "Loudspeaker System with Improved Sound."

[0057] Collar 216 further includes a stabilizing tab 226 extending substantially horizontally from sidewall 222. As shown in FIG. 8A, stabilizing tab 226 interfaces with flexible printed circuit 136, serves to stabilize flexible printed circuit 136, provides protection between the electrical connection between leads 134 and contact pads 138, and maintains the positions of collar 216 and coil assembly 130 in speaker 210. Stabilizing tab 226 is affixed to flexible printed circuit 136 using an adhesive 142 (see FIG. 3), such as, for example, glue, tape, or other adhesives known in the art.

[0058] Another embodiment of collar 316 of the invention is illustrated in FIGS. 9A, 9B and are described below. Some features of one or more of collars 216 and 316 are common to one another and, accordingly, descriptions of such features in one embodiment should be understood to apply to other embodiments. Furthermore, particular characteristics and aspects of one embodiment may be used in combination with, or instead of, particular characteristics and aspects of another embodiment.

[0059] Collar 316 has a first portion 318 that is substantially horizontal and substantially parallel with a pot plate 180. A substantially rectangular opening 320 is provided in first portion 318 through which a coil 132 may translate during operation of a speaker 110. First portion 318 serves as a rim to which the outer perimeter of a membrane 112 is affixed typically, for example, by glue or adhesive. Extending downward and substantially perpendicular from the sides of first portion 318 of collar 316 is a second portion, shown as sidewall 322. Sidewall 322 extends around the perimeter of collar 316.

[0060] Sidewall 316 includes a population of openings 324 extending through sidewall 322 proximate the corners of collar 316. Openings 324 are shown as slots arranged in columns. The slot openings 324 are shown as extending from the terminal end of sidewall 322 up toward first portion 318 of collar 316. In various embodiments, for example, openings 324 may be laser cut into sidewall 322. Openings 324 serve as side vents which permit airflow between a back volume (not shown) and the back volume side of a membrane 112. Openings 324 may be substantially aligned with the gaps between magnets 154 of magnet system 150 and thus a speaker may include a substantially clear air pathway between the back volume and the back volume side of membrane 112. Therefore, openings 324 permit an undistorted vibration of membrane 112 in response to the electrical signal fed into coil 132. With the inclusion of openings 324 on collar 316, back vents are not required in pot plate 180 as shown in FIG. 8B. By not requiring back vents on pot plate 180, the geometry and/or features of pot plate 180 can be simplified as compared to pot plate 80 of prior art speakers, thus reducing component cost. It will be understood however, that in various embodiments, in addition to or alternative to openings on collar 316, back vents may be provided on pot plate 180. [0061] Collar 316 further includes a stabilizing tab 326 extending substantially horizontally from sidewall 322. Stabilizing tab 326 functions the same as stabilizer tab 226 shown in FIG. 8A. Stabilizing tab 326 interfaces with flexible printed circuit 136, serves to stabilize flexible printed circuit 136, provides protection between the electrical connection between leads 134 and contact pads 138, and maintains the positions of collar 316 and coil assembly 130 in the speaker. Stabilizing tab 326 is affixed to flexible printed circuit 136 using an adhesive 142 (see FIG. 3), such as, for example, glue, tape, or other adhesives known in the art. [0062] While embodiments of the audio transducer are shown and described as having a rectangular shape, it will be understood that in other embodiments, the audio transducer may have a variety of shapes, including, but not limited to, circular and ovular. Accordingly, the invention is not limited to audio transducers having a rectangular shape. [0063] Moreover, it should be noted that the invention is not limited to the above mentioned embodiments and exemplary working examples. Further developments, modifications and combinations are also within the scope of the patent claims and are placed in the possession of the person skilled in the art from the above disclosure. Accordingly, the techniques and structures described and illustrated herein should be understood to be illustrative and exemplary, and not limiting upon the scope of the present invention. The scope of the present invention is defined by the appended claims, including known equivalents and unforeseeable equivalents at the time of filing of this application. Although numerous embodiments of this invention have been described above with a certain degree of particularity, those skilled in the art could make numerous alterations to the disclosed embodiments without departing from the spirit or scope of this disclosure.

[0064] In closing, it should be noted that any patent, publication, or other disclosure material, in whole or in part, that is said to be incorporated by reference herein is incorporated herein only to the extent that the incorporated materials does not conflict with existing definitions, statements, or other disclosure material set forth in this disclosure. As such, and to the extent necessary, the disclosure as explicitly set forth herein supersedes any conflicting material incorporated herein by reference. Any material, or portion thereof, that is said to be incorporated by reference herein, but which conflicts with existing definitions, statements, or other disclosure material set forth herein will only be incorporated to the extent that no conflict arises between that incorporated material and the existing disclosure material.

Claims

C l a i m s

An audio transducer, comprising:

a pot plate having a perimeter;

a collar comprising:

a first portion substantially parallel to the pot plate;

a hole extending through the first portion of the collar; and

a second portion extending substantially perpendicular downward from the first portion;

a membrane including a perimeter affixed to the first portion of the collar;

a magnet system comprising one or more magnets arranged on the pot plate, and an air gap formed in the magnet system; and

a coil assembly comprising:

a coil located in the air gap, wherein the coil has a top side affixed to the membrane; and

a pair of electrical leads extending from the coil,

wherein said collar is directly mounted to said pot plate.

An audio transducer according to claim 1 , wherein said collar and said pot plate are made of metal.

An audio transducer according to claim 2, wherein said collar is welded to said pot plate.

An audio transducer according to claim 1, wherein:

the collar comprises a support tab extending substantially perpendicular outward from the second portion; and

the coil assembly comprises a flexible printed circuit having a pair of contact pads, wherein each electrical lead is electrically connected to a respective contact pad, and wherein the support tab of the collar is affixed to the flexible printed circuit.

An audio transducer according to claim 1 , wherein the collar, the membrane and the pot plate are substantially rectangular.

6. An audio transducer, comprising:

a pot plate having a perimeter;

a collar comprising:

a first portion substantially parallel to the pot plate;

a hole extending through the first portion of the collar; and

a membrane including a perimeter affixed to the first portion of the collar;

a magnet system comprising:

a perimeter magnet assembly comprising a plurality of outer magnets arranged proximate the perimeter of the pot plate and a ring plate affixed to the population of outer magnets; and

an air gap formed in the magnet system; and

a coil assembly comprising:

a pair of electrical leads extending from the coil,

wherein said collar is directly mounted to said ring plate.

7. An audio transducer according to claim 6, wherein said collar and said ring plate are made of metal.

8. An audio transducer according to claim 7, wherein said collar is welded to said ring plate.

9. An audio transducer according to claim 6, wherein the collar, the membrane, the pot plate and the ring plate are substantially rectangular.

10. An audio transducer according to claim 6, wherein said collar is also directly mounted to said pot plate. An audio transducer according to claim 10, wherein said collar, said pot plate and said ring plate are made of metal.

An audio transducer according to claim 11 , wherein said collar is welded to said pot plate and to said ring plate.