JP4867555B2 - Speaker and electronic device using it - Google Patents

Description

  The present invention relates to a thin type speaker and an electronic apparatus using the same.

  Since electronic devices such as portable devices are required to be thin, a speaker built in the main body is also required to be thin.

In order to reduce the thickness of the speaker, it is natural to reduce the size of the magnet for forming the magnetic circuit. However, if the magnet is made smaller, the magnetic force becomes smaller, resulting in sound output. Since it becomes small, the magnet cannot actually be made very small (for example, such a prior art is described in Patent Document 1 below).
JP 2005-51283 A

  As described above, the type of speaker built into an electronic device such as a portable device has been conventionally reduced in thickness. However, in order to avoid a decrease in audio output, the magnet cannot actually be made too small. As a result, there has been a problem that thinning which can be satisfactorily satisfied has not been achieved.

  Therefore, the present invention aims to reduce the thickness and to suppress a decrease in audio output.

In order to achieve this object, the present invention provides a case, first and second plate magnets arranged in a horizontal direction or a substantially horizontal direction via a magnetic gap in the case, and the magnetic gap. The first plate-shaped magnet has a magnetic pole formed at the plate end, and the second plate-shaped magnet has a thickness thereof. In a speaker in which magnetic poles are formed at both ends in a direction, a magnetic plate provided below the second plate magnet, a first magnetic ring provided on an outer peripheral portion of the magnetic plate, and a second magnetic ring mounted on the outer peripheral portion of the diaphragm is provided, the first magnetic ring is provided on the lower side of the outer peripheral portion of the front Kifu dynamic plate, the voice coil portion in the magnetic gap This voice coil The magnetic circuit of the speaker includes the first plate magnet, the magnetic plate, the first and second magnetic rings, and the second plate magnet. in is formed, the outer peripheral casing portion of the second plate-shaped magnet of the case is provided with a rear sound emission hole.

As described above, the present invention includes the first and second plate magnets arranged in the horizontal direction or the substantially horizontal direction through the magnetic gap, the voice coil movably arranged in the magnetic gap, and the voice coil. And the first plate magnet forms a magnetic pole at the plate end, and the second plate magnet forms a magnetic pole at both ends in the thickness direction. A magnetic plate provided on the lower side of the second plate-shaped magnet; a first magnetic ring provided on an outer peripheral portion of the magnetic plate; and a first plate mounted on the outer peripheral portion of the diaphragm. a second magnetic material ring is provided, by the first magnetic ring is provided on the lower side of the outer peripheral portion of the front Kifu dynamic plate, the magnetic circuit of the speaker, and the first plate-shaped magnet and said magnetic plate The first and second magnetic rings and the second plate magnet are formed. In the voice coil portion in the magnetic gap, the magnetic flux is substantially orthogonal to the voice coil portion, so that the thickness can be reduced and the first and second plate magnets are arranged on both sides of the magnetic gap. By doing so, it is possible to increase the magnetic force and increase the sound output.

  In addition, the case portion on the outer periphery of the second plate-shaped magnet is provided with a back sound emitting hole, so that the thickness of the case can be reduced by placing the back side of the case close to the installation surface of the electronic device. Of course, since the rear sound emitting hole is provided, it is possible to suppress an increase in the vibration load of the diaphragm as the thickness is reduced.

  Hereinafter, an embodiment of the present invention will be described using a cellular phone as an example of an electronic device with reference to the accompanying drawings.

  In FIG. 1, reference numeral 1 denotes a main body, and a lid 2 is coupled to the main body 1 so as to be freely opened and closed. When viewed from the back side in FIG. 1, the main body 1 is provided with operation buttons (not shown), and the lid 2 is provided with a liquid crystal display (not shown), as in a general mobile phone. It has been.

  Further, two covers 3 are provided on the outer surface side of the main body 1 as shown in FIG. 1, and the speaker 4 shown in FIGS. 2 and 3 is mounted in the main body 1 on the back side of these covers 3. .

  As shown in FIG. 3, the speaker 4 is formed of a surface-side plate 5 made of stainless steel 301 which is a non-magnetic material, a plate 6 made of cold-rolled steel plate which is a magnetic material, and the following frame 13. In the case 4A, the second plate magnet 7 made of neodymium in order from the plate 6 side to the plate 5, the ring 8 formed of a cold-rolled steel plate as a magnetic material, and the diaphragm formed of a PEI resin film 9, a voice coil 10 formed of copper wire, a ring 11 formed of a cold-rolled steel plate as a magnetic material, and two neodymium first plate magnets 12 are sequentially arranged. .

  A front-side sound emission hole 5A is provided on the surface of the plate 5, and the outer peripheral portion is covered with the resin frame 13 as shown in FIGS.

  As shown in FIGS. 3, 5, and 6, the plate 6 has an oval shape, and the upper surface of the rectangular fixing portion 6 </ b> A in the longitudinal central axis portion has a rectangular plate-shaped magnet 7 below it. The plane is fixed by an adhesive (not shown), and rectangular openings 6B are formed on both sides of the fixed portion 6A.

  A ring 8 is fixed to the outer peripheral portion of the plate 6 so that magnetic flux can pass therethrough.

  Further, the outer periphery of the diaphragm 9 is placed on the ring 8, and the ring 11 is placed on the outer periphery of the diaphragm 9.

  Further, the upper surface of the two plate magnets 12 is fixed to the lower surface of the plate 5 facing the opening 6B of the plate 6 with an adhesive (not shown) above the diaphragm 9. In addition, each outer peripheral surface of the two plate-like magnets 12 has a part of an adhesive (not shown) for bonding the upper surface of the two plate-like magnets 12 to the lower surface portion of the plate 5. By entering between the outer peripheral surface of each of the magnets 12 and the inner peripheral surface of the frame 13, it is also fixed to the frame 13 portion.

  In addition, an elliptical voice coil 10 is fixed to a portion of the upper surface of the diaphragm 9 corresponding to the outer periphery of the plate magnet 7 as shown in FIG.

  In the state configured as described above, the two plate magnets 12 made of neodymium are magnetized such that the inner end in the longitudinal direction is an N pole and the outer end is an S pole as shown in FIG.

  Further, as shown in FIG. 7, the neodymium plate magnet 7 is magnetized such that the surface side in the thickness direction is an S pole and the lower surface side in the thickness direction is an N pole.

  As a result, as shown in FIGS. 4 and 7, the magnetic flux emitted from the N pole inside each of the two plate magnets 12 made of neodymium (in FIG. 4, one plate magnet is used in order to avoid the complexity of the drawing. (Only the magnetic flux from 12 is shown) travels substantially horizontally inward, crosses the voice coil 10 in a substantially orthogonal state, and then enters the S pole on the upper surface of the plate magnet 7 (note that Although the plate-like magnet 12 and the plate-like magnet 7 are described as being arranged in a horizontal or substantially horizontal state, this substantially horizontal state means the plate-like magnet 12 and the plate-like magnet 7 as shown in FIG. This includes a state in which a part of the thickness direction overlaps in the horizontal direction, and a state in which the both do not overlap in the thickness direction but partly in the horizontal direction. It is important to make sure that the Is intended to be set).

  Thereafter, the magnetic flux emitted from the N pole on the lower surface of the plate-shaped magnet 7 travels through the rectangular fixed portion 6A of the plate 6, enters the ring 11 after passing through the outer periphery of the ring 8 and the diaphragm 9, and then enters this ring. For example, after a quarter of a round travels 11, it enters the outer peripheral S pole of the plate magnet 12 fixed to the inner periphery of the ring 11 as shown in FIG. 6.

  The flow of the magnetic flux directly becomes a magnetic circuit, and a magnetic gap is formed between the inner N pole of the plate magnet 12 and the upper surface S pole of the plate magnet 7 in the magnetic circuit. A driving force is applied, whereby vibration is transmitted to the diaphragm 9 to which the voice coil 10 is fixed, and sound output is generated.

  Here, the progression of the magnetic flux in the magnetic gap will be described again.

  The magnetic flux emitted from the N pole inside each of the plate magnets 12 shown in FIGS. 4 and 7 travels substantially inward in the magnetic gap and crosses the voice coil 10 in a substantially orthogonal state. This is very important for increasing the field driving force, and is a major feature of the present embodiment.

  In the present embodiment, the reason why the magnetic flux travels substantially inward in the magnetic gap and crosses the voice coil 10 in a substantially orthogonal state will be considered.

  Generally speaking, the magnetic flux emitted from the N pole of the plate magnet 12 tends to travel obliquely toward the S pole on the upper surface of the plate magnet 7 with a short distance (in this case, the magnetic flux passes through the voice coil 10). In this embodiment, as a result, the magnetic flux is lifted by the magnetic gap by receiving the repulsion of the N pole on the lower surface of the plate magnet 7. In FIG. 7, it is considered to travel substantially horizontally as shown in FIG. 7 and cross the voice coil 10 in a substantially orthogonal state.

  In the present embodiment, since the plate magnets 12 and 7 are provided on both sides of the magnetic gap as described above, the so-called magnetic force is increased, and as a result, the sound output by the diaphragm 9 can be increased.

  Further, since the plate-like magnets 12 and 7 for increasing the magnetic force are literally plate-like and thin themselves, as a result, the overall shape can be made very thin.

  Further, since the two plate-like magnets 12 provided in this way have their upper surface having a large surface area fixed to the lower surface portion of the plate 5 with an adhesive (not shown), vibration and impact applied to the case 4A. The strength against is increased.

  Further, since the plate 5 is made of a non-magnetic material, even if the entire upper surface of the plate magnet 12 having both ends of the N pole and the S pole is covered, no magnetic short circuit is caused.

  Further, since the lower surface of the plate magnet 7 having a large surface area is fixed to the upper surface portion of the magnetic plate 6 with an adhesive (not shown), the strength against vibration and impact applied to the case 4A is increased. Furthermore, since the plate 6 is made of a magnetic material, even if it covers the entire lower surface of the plate magnet 7 whose upper and lower ends are S and N poles, the formation of the magnetic circuit shown in FIG. 4 is not hindered.

  Further, in the present embodiment, since the rear sound emitting hole 13A is provided in the outer peripheral portion of the plate magnet 7 of the case 4A, specifically, the frame 13 portion, this vibration is caused by the vibration of the diaphragm 9. Air from the back side of the plate 9 is discharged out of the frame 13 through the back sound emitting hole 13A, and this leads to suppression of an increase in vibration load accompanying the reduction in thickness.

  Further, by providing the rear sound emitting hole 13A, the frame 6 can be placed in contact with the installation portion of the electronic device, which further contributes to the reduction in thickness.

  As is apparent from FIGS. 6 and 7, the diaphragm 9 covers the front side of the plate magnet 7 and the outer periphery extends to the back side of the plate magnet 12 through a magnetic gap. However, in this extended portion, that is, in the outer peripheral direction of the plate-like magnet 7, it protrudes to the front side of the case 4 </ b> A, thereby ensuring a ventilation path to the rear sound emitting hole 13 </ b> A. ing.

  As described above, the present invention includes the first and second plate magnets arranged in the horizontal direction or the substantially horizontal direction through the magnetic gap, the voice coil movably arranged in the magnetic gap, and the voice coil. The first plate magnet has a magnetic pole formed at its plate end, and the second plate magnet has a magnetic pole formed at both ends in the thickness direction, and the magnetic gap In the voice coil portion, the speaker has a configuration in which the magnetic flux is substantially orthogonal to the voice coil portion, and is arranged in the horizontal direction or the substantially horizontal direction through the magnetic gap, so that the thickness can be reduced. Moreover, since the first and second plate magnets are arranged on both sides of the magnetic gap, it is possible to increase the magnetic force and increase the sound output.

  In addition, the case portion on the outer periphery of the second plate-shaped magnet is provided with a back sound emitting hole, so that the thickness of the case can be reduced by placing the back side of the case close to the installation surface of the electronic device. Of course, since the rear sound emitting hole is provided, it is possible to suppress an increase in the vibration load of the diaphragm as the thickness is reduced.

  As a result, it becomes very easy to use for portable devices such as mobile phones.

The perspective view which applied one Embodiment of this invention to the mobile telephone The perspective view which applied one Embodiment of this invention to the mobile telephone Exploded perspective view of the speaker Exploded perspective view of the speaker Sectional view of the speaker cut in the longitudinal direction Sectional view of the speaker cut in the short direction 6 is an enlarged cross-sectional view of part A

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Main body 4 Speaker 4A Case 7 2nd plate-shaped magnet 9 Diaphragm 10 Voice coil 12 1st plate-shaped magnet 13A Back surface sound emission hole

Claims (4)

A case, first and second plate magnets disposed in a horizontal or substantially horizontal direction via a magnetic gap in the case, a voice coil movably disposed in the magnetic gap, and the voice coil In the speaker, the first plate magnet has a magnetic pole formed at the plate end, and the second plate magnet has a magnetic pole formed at both ends in the thickness direction. A magnetic plate provided below the second plate magnet, a first magnetic ring provided on the outer periphery of the magnetic plate, and a second mounted on the outer periphery of the diaphragm. provided a magnetic ring, said first magnetic ring is provided on the lower side of the outer peripheral portion of the front Kifu dynamic plate, wherein the voice coil portion in the magnetic gap is substantially perpendicular magnetic flux with respect to the voice coil section When configured to In addition, the magnetic circuit of the speaker is formed by the first plate magnet, the magnetic plate, the first and second magnetic rings, and the second plate magnet, and the second plate of the case speaker having a rear sound holes on the outer casing portion of the Jo magnets. The rectangular first plate magnets are arranged on both sides in the longitudinal direction of the rectangular second plate magnet via the magnetic gaps so that the longitudinal directions thereof are substantially opposed to each other, and the voice coil has a substantially planar shape. The speaker according to claim 1, wherein the speaker has an oval shape, and the long sides on both sides of the substantially oval voice coil are arranged in the magnetic gap on both sides of the rectangular second plate magnet. The speaker according to claim 1, wherein the diaphragm is projected to the front side of the case in the outer peripheral direction of the second plate magnet. The electronic device which incorporated the speaker as described in any one of Claims 1-3 in the main body.

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