JP2008092040A - Speaker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thin type speaker which is made thin. <P>SOLUTION: A through hole 18 for back pressure adjustment is bored in a lower case 5 holding an outer periphery of a diaphragm 13 provided with a voice coil 14 disposed in a magnetic gap formed between first and second bar magnets 11 and 15. Consequently, the diaphragm is prevented from sticking on the first and second bar magnets owing to a decrease in space between the diaphragm and the first and second bar magnets accompanying the thickness reduction. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a thin type speaker.

  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 conventional technique 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, but in order to avoid a decrease in audio output, the magnet cannot actually be made too small. However, as a result, there has been a problem that the thickness has not been sufficiently satisfied.

  Therefore, the present invention aims to reduce the thickness and enhance the sound output.

  In order to achieve this object, the speaker of the present invention has a first bar-shaped magnet and a magnetic gap formed between the first bar-shaped magnet and disposed in parallel to the first bar-shaped magnet. A second rod-shaped magnet arranged in a horizontal direction or a substantially horizontal direction via the first magnetic pole surface, and one magnetic pole surface of the first rod-shaped magnet and one magnetic pole surface of the second rod-shaped magnet are magnetically coupled to each other. And a top and bottom case made of a non-magnetic material that accommodates the first and second rod-shaped magnets and the yoke so as to form spaces at both longitudinal ends of the first and second rod-shaped magnets. A vibration plate disposed in a space in the upper surface direction of the first bar-shaped magnet and a space in the lower surface direction of the second bar-shaped magnet and supported on the outer periphery thereof and capable of vibrating in the vertical direction; and fixed to the vibration plate And a voice coil disposed in the magnetic gap A sound emitting hole is formed at both ends of the front surface of the upper and lower case so as to communicate with spaces formed at both end portions of the first and second bar magnets in the upper and lower case, and the lower case A through-hole for adjusting the back pressure is provided.

  As described above, the present invention is a vibration in which the first and second rod-shaped magnets are arranged in the horizontal direction or substantially in the horizontal direction of the magnetic gap via the magnetic gap, and the voice coil arranged in the magnetic gap is fixed. Since the plate is disposed in the space in the upper surface direction of the first bar-shaped magnet and in the space in the lower surface direction of the second bar-shaped magnet, the thickness can be reduced. In addition, sound emitting holes are formed at both ends of the front surface of the upper and lower cases made of a non-magnetic material that accommodates the first and second bar magnets so as to form spaces at both ends of the first and second bar magnets. Since the sound emitting hole communicates with the space at both ends of the first and second rod-shaped magnets, the space in the lower surface direction of the second rod-shaped magnet in which the diaphragm is disposed is formed as a relatively large capacity. It is possible and can increase the sound output.

  Moreover, since the diaphragm is provided with a through-hole for back pressure adjustment, the first and second diaphragms due to the reduction in the space between the diaphragm and the first and second rod-shaped magnets due to the reduction in thickness. Sticking to the second rod-shaped magnet can be prevented.

  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. . A speaker 3 is built in the back side of the main body 1, and a sound emitting hole provided in the case of the speaker 3 communicates with a sound emitting hole 4 provided on the outer surface of the main body 1.

  As shown in FIG. 2, the speaker 3 has sound emitting holes 7 at both ends of the front surface of the lower case 5 and the upper case 6 made of a nonmagnetic material divided into upper and lower parts, Communicating with Further, the speaker 3 is provided with a terminal plate in the vicinity of the back side of the upper surface of the upper case 6, and a signal from an external amplifier is input to the joint 8a where the start and end of the voice coil are soldered to the terminal plate. The terminal part 8b to be formed is formed.

  As shown in FIGS. 3, 4, and 5, the speaker 3 has a first bar-shaped magnet 11 joined to the center of the U-shaped yoke 10 so as to be parallel to the shoulder 10 a of the yoke 10. A lower plate 12 made of a magnetic material is joined to the upper surface of the first bar-shaped magnet 11. The yoke 10 assembled with the first bar-shaped magnet 11 and the lower plate 12 in this way is housed in the center of the bottomed rectangular lower case 5 so that the lower surface of the yoke 10 and the first bar-shaped magnet 11 are accommodated. Vibration spaces are secured at both ends in the longitudinal direction. Further, a back pressure adjusting through hole 18 is formed on the back surface of the lower case 5.

  Here, the yoke 10 is coupled to a groove portion 5a provided in the lower case 5, and the upper surface of the shoulder portion 10a is flush with the upper surface of the step portion 5b provided in the case 5, and will be described later. It is designed to be used as a margin for joining plates.

  In addition, the speaker 3 has an elliptical voice coil 14 joined to the diaphragm 13, and a support portion 13a on the outer periphery thereof is joined to the joint on the lower case 5 side by an adhesive.

  Before and after the first bar-shaped magnet 11, a second bar-shaped magnet 15 is arranged so as to be parallel to the first bar-shaped magnet 11, and a predetermined magnetic gap is provided between the first bar-shaped magnet 11 and the first bar-shaped magnet 11. Is forming. Here, as shown in FIG. 3, the second bar-shaped magnet 15 is disposed obliquely above the first bar-shaped magnet 11.

  The upper case 6 combined with the lower case 5 includes a U-shaped frame main body 6a in which the terminal plate is insert-molded, a non-magnetic upper lid 6b for closing an upper window of the case main body 6a, and the case main body. The front lid 6c closes the front window center of 6a, and has a window portion for forming sound emission holes 7 at both ends of the front lid 6c. Inside the upper case 6, two plate-like yokes 16 are joined in parallel with the first and second rod-like magnets 11, 15, and the second rod-like magnets are joined to the inner surface of the yoke 16. 15 are respectively joined.

  The speaker 3 is assembled with the diaphragm 13 with the voice coil 14 assembled to the lower case 5 side after the yoke 10 with the first bar magnet 11 and the upper plate 12 assembled with the lower case 5, and then The upper case 6 assembled with the second bar-shaped magnet 15 is assembled to the lower case 5 for assembly.

  By this assembly, the diaphragm 13 is arranged in the space in the upper surface direction of the first bar-shaped magnet 11 and in the space in the lower surface direction of the second bar-shaped magnet 15. Then, both end portions of the diaphragm 13 in the longitudinal direction are arranged in a relatively large vibration space where the first and second rod-shaped magnets 11 and 15 are not present.

  On the other hand, the upper surface in the longitudinal direction of the yoke 16 on the upper case 6 side is closely opposed to the shoulder portion 10a of the yoke 10 via the support portion 13a of the diaphragm 13, and the first and second bar magnets 11 and 15 are opposed to each other. Are magnetically coupled.

  By configuring the speakers in the rectangular upper and lower cases 5 and 6 as described above, the space factor is improved and the structure is small and thin, which is advantageous for improving the sound pressure level.

  That is, as described above, by having two or more bar-shaped magnets, the energy of the magnetic circuit is improved, and by arranging these bar-shaped magnets obliquely upward to form a magnetic gap, the thickness and size can be reduced. Realized.

  In addition, the space factor is improved by making the outer shape rectangular, and the effective utilization and efficiency of the magnetic circuit space are improved by using magnetic circuit components such as bar magnets, plates, and yokes.

  By the way, in the thinned speaker, the space of the magnetic gap between the first rod-shaped magnet 11 and the second rod-shaped magnet 15 becomes small, and the voice coil disposed in the magnetic gap Since the space between the diaphragm 13 that supports 14 and the first and second rod-shaped magnets 11 and 15 is also narrow, the diaphragm 13 sticks to the first and second rod-shaped magnets 11 and 15. This phenomenon is likely to occur. In particular, this phenomenon becomes remarkable on the back side of the diaphragm 13 (the space on the lower case 5 side), which is a sealed space, but this sticking is achieved by providing the lower case 5 with a through hole 18 for back pressure adjustment. The phenomenon can be prevented.

  In the speaker configured as described above, the first bar-shaped magnet 11 is magnetized in the thickness direction as shown in FIG. 6, and the surface side in the thickness direction is magnetized to the S pole and the lower surface side in the thickness direction is magnetized to the N pole. ing. On the other hand, the second rod-like magnet 15 is magnetized in the short width direction, and the inner side surface in the longitudinal direction is magnetized to the N pole and the outer side surface in the longitudinal direction is magnetized to the S pole.

  As a result, as shown in FIG. 6, the magnetic flux emitted from the N pole inside each of the first bar-shaped magnets 15 (in FIG. 6, only the magnetic flux emitted from one bar-shaped magnet 15 is shown in order to avoid the complicated feeling of the drawing. Is moving inward substantially horizontally, traverses the voice coil 14 in a substantially orthogonal state, and then enters the south pole on the top surface of the bar-shaped magnet 11 (the bar-shaped magnets 15 and 11 are horizontal or Although it is described that they are arranged in a substantially horizontal state, this substantially horizontal state is a state in which the thickness directions of the bar magnets 15 and 11 partially overlap in the horizontal direction as shown in FIG. Although it does not overlap in part in the horizontal direction, it also includes a close state, that is, it is important to advance the magnetic flux so as to be substantially orthogonal to the voice coil 14. ) Is set.)

  Thereafter, the magnetic flux emitted from the N pole on the lower surface of the rod-shaped magnet 11 travels through the yoke 10 and the shoulder 10a of the yoke 10, passes through the yoke 16 magnetically coupled to the shoulder 10a of the yoke 10, and the outer periphery of the rod-shaped magnet 15 It will enter the south pole.

  The magnetic flux flows as it is to form a magnetic circuit, and in this magnetic circuit, the gap between the inner N pole of the bar magnet 15 and the upper surface S pole of the bar magnet 11 forms a magnetic gap. As a result, vibration is transmitted to the diaphragm 13 to which the voice coil 14 is fixed, and sound output is generated.

  In the speaker according to the present invention, both ends in the longitudinal direction of the bar-shaped magnet are used as vibration spaces, and both ends of the front surface in the longitudinal direction of the upper and lower cases are communicated with the vibration spaces as sound emitting holes. A side port can be configured together. As a result, the present invention can be applied to a mobile device such as a mobile phone.

The perspective view of the mobile telephone to which the speaker of one Embodiment of this invention is applied. Perspective view of the speaker Sectional view of the speaker cut in the short direction Sectional view of the speaker cut in the longitudinal direction Assembly perspective view of the speaker The principal part expanded sectional view of the speaker

Explanation of symbols

DESCRIPTION OF SYMBOLS 5 Lower case 6 Upper case 7 Sound emission hole 10 Yoke 11 1st rod-shaped magnet 13 Diaphragm 14 Voice coil 15 2nd rod-shaped magnet 16 Yoke

Claims (2)

The first bar-shaped magnets are arranged in parallel to the first bar-shaped magnets, and are arranged in a horizontal direction or a substantially horizontal direction via a magnetic gap formed between the first bar-shaped magnets. Two rod-shaped magnets, a yoke for magnetically coupling and supporting one magnetic pole surface of the first rod-shaped magnet and one magnetic pole surface of the second rod-shaped magnet, and the first and second rod-shaped magnets An upper and lower case made of a non-magnetic material that accommodates the first and second rod-shaped magnets and the yoke so as to form a space at both ends in the longitudinal direction of the magnet; a space in the upper surface direction of the first rod-shaped magnet; A diaphragm that is disposed in a space in the lower surface direction of the second bar-shaped magnet and is supported on the outer periphery thereof and can vibrate in the vertical direction, and a voice coil that is fixed to the diaphragm and disposed in the magnetic gap. The upper and lower cases are provided at both ends of the front surface of the upper and lower case. It said first inner, a sound output hole so as to communicate with the space which is formed at both ends portion of the second rod-shaped magnet is formed, and a speaker having a through hole for a back pressure regulator to the lower case. The speaker according to claim 1, wherein the first bar-shaped magnet is magnetized in the thickness direction, and the second bar-shaped magnet is magnetized in the short width direction.

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