JP2007049326A - Flat speaker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flat speaker in which disconnection is rarely generated on a lead part of a voice coil. <P>SOLUTION: The flat speaker is provided with: a diaphragm constituted of voice coils on which at least one and more spirals are formed, a lead part drawn out from the voice coils and reinforced by a reinforcing part and a feeder connected to the end part of the lead part; an edge part on which the diaphragm is supported; and a yoke, in which the edge part is supported, provided with permanent magnets arranged on positions opposed to respective voice coils. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a thin flat speaker.

  In recent years, the development of flat speakers that respond to the need for thin and lightweight LCD televisions and automobiles has been underway. For example, the flat speaker disclosed in Patent Document 1 generates a driving force on the entire surface of a planar vibration film, and therefore emits a plane wave as a surface sound source and has a flat phase. Furthermore, unlike conventional cone-type speakers, paper is not used, so heat resistance and moisture resistance are excellent. Underwater driving is possible, and howling is unlikely to occur because individual sound cells are small. Furthermore, it has the outstanding features that it is ultra-thin and lightweight with a thickness of 1 cm or less, has a small number of parts, and has a very simple structure.

  Here, the configuration of a conventional flat speaker will be described in detail with reference to the drawings. FIG. 6 is a cross-sectional view showing an example of a conventional flat speaker. A flat speaker 500 shown in FIG. 6 includes a flat yoke 1 made of an iron plate (ferromagnetic metal plate) and a plurality of permanent magnets 3 attached to one surface of the yoke 1 with the magnetic axis perpendicular. The permanent magnets 3 are attached so that the polarities of adjacent magnets are opposite to each other at a predetermined interval in the plane direction of the yoke.

Further, the flat speaker 500 is provided with an auxiliary portion (hereinafter referred to as an edge portion) 5 which is joined to a shelf portion 1b of the yoke on the peripheral wall portion 1a of the yoke 1 and a part thereof is arched, and an edge portion 5 is provided. There is provided a diaphragm 7 that is joined with a sticky material such as an adhesive via a magnetic pole face of the permanent magnet 3 and supported in a movable state at a desired distance. In FIG. 6, the edge portion 5 is indicated by hatching.

The diaphragm 7 is formed of an insulating base film or the like, and a voice coil in which at least one or more spirals that are spirally or meandered corresponding to the permanent magnet 3 are formed on both surfaces (or even one surface) of the diaphragm 7. 9 is formed. All the voice coils 9 are connected so that currents in the same direction flow in adjacent sides of the adjacent voice coils 9. In addition, a plurality of holes (not shown) are formed between the permanent magnets 3 in the yoke 1 in order to adjust fluctuations in air pressure caused by the vibration of the diaphragm 7.

FIG. 7 is a plan view of the flat speaker 500 described above. In FIG. 7, a frame-shaped edge portion 5 is joined to the yoke 1 according to its shape, and the diaphragm 7 is joined to the edge portion 5. The diaphragm 7 is provided with five voice coils 9 in the longitudinal direction and three voice coils 9 in the vertical direction in close contact with each other on a plane, and a voltage is applied to the voice coil 9 through a feeder line 11.

In the flat speaker 500 configured as described above, a current flows through each voice coil 9, and the diaphragm 7 is driven up and down substantially over the entire surface.
JP 2003-284187 A

  In the above-described flat speaker 500, in order to increase the conversion efficiency for converting an electric signal into vibration of the diaphragm 7, it is effective to reduce the weight of the diaphragm 7 by thinning the insulating base film, but the amount of amplitude increases. As a result, there is a problem that stress concentration occurs and the voice coil 9 is disconnected.

  In particular, the vicinity of the feed wire attachment portion (hereinafter referred to as a lead portion) 13 that is electrically connected to the voice coil 9 provided near the end of the diaphragm 7 is highly rigid on the flexible diaphragm 7. Since the feeder line 11 is arranged, stress concentration is likely to occur and the voice coil 9 is likely to be disconnected.

  The present invention has been made in view of the above-described problems, and provides a flat speaker in which disconnection of a lead portion of a voice coil is unlikely to occur.

  A first aspect of the flat speaker according to the present invention includes a voice coil in which at least one spiral is formed, a lead portion that is pulled out from the voice coil and reinforced by the reinforcement portion, and is provided at an end portion of the lead portion. A vibration plate comprising a power supply line, an edge portion on which the vibration plate is supported, and a yoke on which the edge portion is supported and a permanent magnet provided at a position facing the voice coil. This is a featured flat speaker.

  The 2nd aspect of the flat speaker which concerns on this invention is a flat speaker characterized by a reinforcement part being an edge part.

  The 3rd aspect of the flat speaker which concerns on this invention is a flat speaker characterized by the reinforcement part being a resin material.

  The 4th aspect of the flat speaker which concerns on this invention is a flat speaker characterized by a reinforcement part being an adhesive agent.

  According to a fifth aspect of the planar speaker of the present invention, the reinforcing portion is symmetrical with the first reinforcing portion covering the lead portion and the vicinity of the lead portion, and extended in the longitudinal direction, facing the first reinforcing portion. It is a 2nd reinforcement part which becomes the planar speaker characterized by the above-mentioned.

  A sixth aspect of the flat speaker according to the present invention is the flat speaker characterized in that the reinforcing portion covers the lead portion and the vicinity of the lead portion.

  A seventh aspect of the flat speaker according to the present invention is the flat speaker, wherein the reinforcing portion covers the vicinity of the lead portion including the voice coil and the lead portion.

  As described above, by fixing the lead portion of the flat speaker of the present invention with the reinforcing member, stress concentration in the lead portion can be avoided and disconnection can be prevented. Further, the configuration of the reinforcing member can prevent the diaphragm from being reduced in weight and sound quality from being deteriorated.

  Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 1 to 5.

(First embodiment)
FIG. 1 is a cross-sectional view for explaining a schematic configuration of a flat speaker according to the first embodiment of the present invention. Examples of the flat speaker include a flat speaker having an outer dimension of 50 mm × 90 mm × 8 mm.

  A flat speaker 100 shown in FIG. 1 has a flat yoke 1 made of a soft iron plate (ferromagnetic metal plate), and a plurality of permanent magnets 3 are provided thereon. The plurality of permanent magnets 3 are arranged such that the magnetic pole surfaces of the adjacent permanent magnets 5 are opposite to each other at a predetermined distance. The permanent magnet 3 can have a size of, for example, 7 mm × 7 mm × 2.4 mm.

  Further, the planar speaker 100 is joined to a yoke shelf 1b on the peripheral wall 1a of the yoke 1 and has a frame-shaped edge portion 5 having a part of an arch shape, and an adhesive or the like via the edge portion 5. A diaphragm 7 is provided which is bonded with an adhesive material and is supported in a movable state while maintaining a desired distance from the magnetic pole surface of the permanent magnet 3.

  The diaphragm 7 has a voice coil 9 in which at least one spiral is formed, and each voice coil 9 is provided at a position facing the magnetic pole surface of the permanent magnet 3. Here, the voice coil 9 refers to one obtained by counting each spiral as one voice coil, and the same applies to the following embodiments. The diaphragm 7 and the permanent magnet 3 are arranged so as to be substantially parallel with a predetermined distance therebetween. Further, a lead portion 13 is drawn out from the voice coil 9 and is connected to a power supply line 11 provided at an end portion of the lead portion 13.

  In the present embodiment, the diaphragm 7 has the spiral voice coil 9 in which at least one spiral is formed. However, the present invention is not limited to this. Alternatively, the voice coil 9 may be provided on the insulating base film by meandering, for example. Further, the permanent magnet 3 is not limited to a plurality of permanent magnets 3 provided.

  FIG. 2 is a plan view of the flat speaker 100 according to the first embodiment. As shown in FIG. 2, the planar speaker 100 according to the present embodiment has a total of 15 3 × 5 boil coils 9 arranged on both surfaces of the diaphragm 7. As is clear from FIG. 2, in this embodiment, the width of the edge portion 5 is expanded as a whole to cover the diaphragm 7. As a result, the lead portion 13 and the vicinity thereof are reinforced by the edge portion 5.

  Further, in the flat speaker 100 configured as described above, when the diaphragm 7 vibrates up and down, the air on the front surface of the diaphragm 7 vibrates and emits a sound. The air on the back also vibrates. In the present embodiment, an air hole (not shown) is provided between the permanent magnets 3 in the yoke 1 so that the air on the back surface of the diaphragm 7 can escape from the flat speaker 100 to the outside.

  That is, between the roll part 6 and the voice coil 9 of the edge part 5, the edge part 5, the diaphragm 7, and the edge part 5 are reinforced by an adhesive, and as a result, the lead part 13 is reinforced. Will be.

  As a result of adopting the above-described configuration for the flat speaker 100, a sound was generated by applying an electric energy of 20W, and a heat cycle test (cooling shock test) was performed in the range of -10 ° C to 60 ° C. Although the lead portion 13 was disconnected in 100 hours, a good result was obtained that the lead portion 13 did not break even when an electric energy exceeding about 1000 hours was applied under the same conditions.

(Second Embodiment)
Next, a second embodiment of the flat speaker according to the present invention will be described. In addition, the same code | symbol is attached | subjected to the structure similar to each part of the planar speaker shown by FIG. 1, and the description is abbreviate | omitted.

  The flat speaker 200 shown in FIG. 3 expands the width of the edge portion 5 at the portion of the diaphragm 7 that covers the two lead portions 13 and the vicinity thereof, and reinforces the periphery of the lead portion 13. In the flat speaker 200 according to the second embodiment, the width of the edge portion 5 is expanded for the diaphragm 7 including the two lead portions 13 in the first embodiment, and the lead portion 13 and the vicinity thereof are reinforced. The weight of the minute edge is increased, and the sound quality may be deteriorated.

In the present embodiment, the above-described portion is expanded to further reduce the weight of the edge portion 5 compared to the first embodiment and prevent deterioration in sound quality. Also in this embodiment, as a result of conducting a heat cycle test under the same conditions as in the first embodiment, the same effect could be obtained.
(Third embodiment)
Next, a third embodiment of the flat speaker according to the present invention will be described. In addition, the same code | symbol is attached | subjected to the structure similar to each part of the planar speaker shown in FIG. 1, and the description is abbreviate | omitted.

  A flat speaker 300 shown in FIG. 4 includes two lead portions 13 and a first edge portion 5a in the vicinity thereof in the diaphragm 7, and extends in the longitudinal direction to face the first edge portion 5a. The second edge portion 5b which is symmetrical to the left and right is provided to reinforce the periphery of the lead portion 13.

  In the flat speaker 300 according to the third embodiment, the edge portion 5 is expanded with respect to the two lead portions 13 and the vicinity thereof in the second embodiment. As a result, the shape of the expanded edge portion 5 is asymmetrical left and right. Become. Therefore, there is a possibility that a phenomenon in which the diaphragm 7 does not vibrate evenly may occur, and the sound quality may be deteriorated. In the present embodiment, the edge portion 5 is expanded by extending the edge portion 5 with respect to the two lead portions 13 and the portion in the vicinity thereof, and the portion that is extended in the longitudinal direction and is symmetrical with respect to the portion. The shape of the sound is symmetrical and prevents deterioration in sound quality. Also in this embodiment, as a result of conducting a heat cycle test under the same conditions as in the first embodiment, the same effect could be obtained.

(Fourth embodiment)
Next, a fourth embodiment of the flat speaker according to the present invention will be described. In addition, the same code | symbol is attached | subjected to the structure similar to each part of the planar speaker shown by FIG. 1, and the description is abbreviate | omitted.

  FIG. 5 shows that only a portion of the diaphragm 7 covering the two lead portions 13 is coated with an ultra-fine foam sheet, a flexible, lightweight, heat-resistant plastic member such as MCPET (registered trademark), or an adhesive. This reinforces the periphery of the lead part.

  In this embodiment, the same part as that of the second embodiment is reinforced, and the weight can be reduced as compared with the above-described embodiment. Furthermore, by using a member having flexibility, light weight, and heat resistance instead of the edge portion 5 used as the reinforcing member in the third embodiment, it is possible to reinforce more strongly than the second embodiment. Also in this embodiment, as a result of conducting a heat cycle test under the same conditions as in the first embodiment, the same effect could be obtained.

  In the first to fourth embodiments described above, the reinforcing portion such as the extended edge portion can include a voice coil. By including the voice coil, the stress generated in the lead portion when the diaphragm swings is avoided, and the reliability of the lead portion is improved.

  Further, in the above-described flat speaker, the number of voice coils is a design matter of those skilled in the art, and the number is not limited. Further, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.

  By fixing the lead portion of the flat speaker of the present invention with the reinforcing member, it is possible to avoid stress concentration in the lead portion and prevent disconnection, and the industrial applicability is high.

It is sectional drawing of the planar speaker in 1st Embodiment. It is a top view of the flat speaker in a 1st embodiment. It is a top view of the plane speaker in a 2nd embodiment. It is a top view of the plane speaker in a 3rd embodiment. It is a top view of the plane speaker in a 4th embodiment. It is sectional drawing of the conventional flat speaker. It is a top view of the conventional flat speaker.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Yoke 1a Peripheral wall part of 1b Yoke shelf part 3 Permanent magnet 5, 5a, 5b Edge part 6 Roll part of edge part 7 Diaphragm 9 Voice coil 11 Feed line 13 Lead part 15 Input terminal 17 MCPET (trademark)
100, 200, 300, 400, 500 flat speaker

Claims (7)

A diaphragm comprising: a voice coil in which at least one spiral is formed; a lead portion drawn out from the voice coil and reinforced by a reinforcement portion; and a feeder line provided at an end portion of the lead portion; ,
An edge portion on which the diaphragm is supported;
A yoke on which the edge portion is supported and a permanent magnet provided at a position facing the voice coil;
A flat speaker. The flat speaker according to claim 1, wherein the reinforcing portion is the edge portion. The flat speaker according to claim 1, wherein the reinforcing portion is a resin material. The flat speaker according to claim 1, wherein the reinforcing portion is an adhesive. The reinforcing part is a first reinforcing part that covers the lead part and the vicinity of the lead part, and a second reinforcing part that is extended in the longitudinal direction and is symmetrical with respect to the first reinforcing part. The flat speaker according to any one of claims 2 to 4, characterized in that: The flat speaker according to any one of claims 2 to 4, wherein the reinforcing portion covers the lead portion and the vicinity of the lead portion.   The flat speaker according to any one of claims 2 to 4, wherein the reinforcing portion covers the vicinity of the lead portion including the voice coil and the lead portion.

Images