JPWO2017145284A1 - Electro-acoustic transducer - Google Patents

Abstract

In an electroacoustic transducer adopting a voice coil diaphragm, by utilizing not only the parallel magnetic field component of the magnetic field formed by the magnet plate but also the perpendicular magnetic field component, a new vibration form is realized to further enhance the performance, An object of the present invention is to provide an electro-acoustic transducer which is diversified and which is excellent in versatility, mass productivity and resource saving. An electro-acoustic transducer comprising a magnet plate and a coil vibrator formed by winding a conductor and disposed in front of the magnet plate, wherein the coil vibrator is inclined with respect to the front surface of the magnet plate By having a vibrating surface or a vibrating surface perpendicular to the front surface of the magnet plate, the vibrating surface is formed in a loop shape, and the vibration of the coil vibrator has at least a component parallel to the front surface of the magnet plate , The utilization efficiency of the magnet can be improved, and the directivity can be greatly improved.

Description

  The present invention relates to an electroacoustic transducer applied to a speaker, headphone, earphone or the like which converts an electric signal into sound, or a microphone, a sound wave sensor or the like which converts received sound into an electric signal.

Conventionally, in an electroacoustic transducer called a Gamuzon type speaker, a flat coil pattern is formed of a conductor corresponding to a voice coil, and a portion generating a driving force is integrated with a diaphragm (hereinafter referred to as "voice coil vibration Plate) is installed in the middle of the pair of magnetic field generators, and the voice coil diaphragm is vibrated in the direction perpendicular to its plane by supplying drive current to the conductor. There is.
The voice coil diaphragm of this gumuzon type speaker is characterized in that the entire surface is driven in the same phase and good transient characteristics can be obtained in a wide band because the conductor is arranged almost in the entire area of the voice coil diaphragm. have.

For example, in (Patent Document 1), the magnetic poles of adjacent strip magnets (or strip regions in a flat plate magnet plate) are alternately arranged, and the entire magnet plate consisting of these many strip magnets is formed in a flat plate shape An electroacoustic transducer is disclosed. The direction (magnetization direction) of the magnetic pole of the strip-shaped magnet is arranged to be perpendicular to the flat plate surface, and a flat voice coil diaphragm is disposed to face the front surface of the flat magnet plate.
Here, in the magnetic field formed by the magnet plate formed in a flat plate shape as a whole, a component parallel to the front surface of the magnet plate is defined as a parallel magnetic field component, and a component perpendicular to the front surface is defined as a perpendicular magnetic field component.

In the electro-acoustic transducer of (Patent Document 1), since the directions of the magnetic poles are alternately made different, many portions where the direction of the magnetic field is reversed and portions where the magnetic field strength is low exist on the voice coil diaphragm. . Therefore, in the component of the magnetic field that can be effectively used for sound generation, that is, in the magnetic field that causes an electromagnetic force to the conductor of the voice coil diaphragm, a magnetic field component that contributes to the generation of sound (hereinafter referred to as "effective magnetic field component") The magnetic field strength of (hereinafter referred to as "effective magnetic field strength") also changed significantly.
Furthermore, in the electro-acoustic transducer of (Patent Document 1), since the planar voice coil diaphragm is disposed parallel to the flat magnet plate, the effective magnetic field component is only the parallel magnetic field component of the magnetic field. . Therefore, when the direction of the magnetic pole of the strip magnet is all perpendicular to the planar voice coil diaphragm, the parallel magnetic field component becomes smaller in the part near the magnetic pole, the effective magnetic field strength becomes lower, and the sound is generated. It becomes an area that can not be used effectively.
Moreover, in the electroacoustic transducer of (Patent Document 1), the winding direction of the conductor is reversed in accordance with the direction of the reversing magnetic field, or the conductor is matched in a region where the effective magnetic field strength is partially present. It was necessary to arrange it. Therefore, the entire surface of the diaphragm can not be made a conductor, and a support member such as a synthetic resin sheet for closing the gap between the conductors is indispensable, and the vibration unique to the support member adversely affects the sound quality. Furthermore, there is a problem that the driving force of each part of the voice coil diaphragm is largely varied, which causes the divided vibration which becomes a big problem for the reproduction of high quality sound.

Next, (Patent Document 2) discloses an electroacoustic transducer in which two types of cylindrical and ring-shaped magnet components are concentrically separated on the center side and the outer periphery side. As a flat voice coil diaphragm, an insulating film in which a conductor is formed in a spiral shape is used, and it is disposed in parallel to the magnet component between the two types of magnet components. Further, each of the two types of magnet components is composed of two magnets, and the magnetization direction of the four magnets in total is perpendicular to the voice coil diaphragm. The two magnets constituting the two types of magnet parts are combined so that their magnetic poles face each other, and the two types of magnet parts are installed so that the polarities are reversed at the center side and the outer peripheral part.
In this electroacoustic transducer, since all the conductors are spirally wound in the same direction, it is possible to use the entire surface of the voice coil diaphragm as the conductor. As a result, it becomes possible to generate a driving force on the entire surface of the voice coil diaphragm, which is effective against the problem as disclosed in Patent Document 1.
However, even in this electro-acoustic transducer, the magnetization direction of the magnet is only perpendicular to the voice coil diaphragm. Therefore, the distribution of the magnetic field formed by each of the two magnets constituting the two types of magnet parts, ie, the four magnets, has a small parallel magnetic field component near the magnetic pole and a low effective magnetic field strength. This is an area that can not be used for the vibration of the voice coil diaphragm. Therefore, the voice coil diaphragm is installed at a position away from the magnetic pole, and it is difficult to obtain high effective magnetic field strength.
Also, because the voice coil diaphragm is installed between the two types of magnet parts on the center side and the outer circumference side, when the area of the voice coil diaphragm is increased, the distance between the magnet parts is increased and the effective magnetic field strength is increased. descend. Therefore, high effective magnetic field strength can not be obtained while securing a sufficient area of the conductor portion.

As described above, in the magnet plate of (Patent Document 1) or (Patent Document 2) in which the magnetization direction is only perpendicular to the voice coil diaphragm, the effective magnetic field component of the magnetic field formed by the magnet plate can not be increased. Since the utilization efficiency of the magnet is poor and the region where the effective magnetic field strength is high is narrowed, there is a problem that a sufficient area can not be secured while using the entire surface of the voice coil diaphragm as a conductor.
Furthermore, since the effective magnetic field intensity can not be increased too much, the conversion efficiency to sound energy (hereinafter referred to as "efficiency") can not be increased.
As a structure adopting a diaphragm equivalent to a voice coil diaphragm in which a portion generating the driving force is integrated with the diaphragm, there is a ribbon type such as a leaf type (Patent Document 5). With these structures, too, the area of the voice coil diaphragm can not be enlarged because the area where the effective magnetic field strength is high can not be increased, and it has been difficult to adopt it as a speaker structure for not only the low band but also the mid band. .
In order to solve these conventional problems, according to the patent application (Patent Document 3) in which the present applicant has earnestly studied and patented, the magnet plate is divided into many partial areas, and each partial area is increased in effective magnetic field component. An electro-acoustic transducer with a magnetization direction is disclosed. The voice coil diaphragm is a flat conductor formed by winding a conductor spirally, and is disposed in parallel with the front of the magnet plate.
In this electroacoustic transducer, since the region where the effective magnetic field strength is high can be broadened, it has become possible to adopt it as a structure of a low frequency range speaker in which the voice coil diaphragm becomes large. In addition, since the effective magnetic field strength can be increased as compared with the cases of (Patent Document 1) and (Patent Document 2), it is possible to increase the efficiency and also improve the utilization efficiency of the magnet.
Furthermore, although it is possible to widen the region where the effective magnetic field strength is high as in (Patent Document 3) and to increase the efficiency, no special shape or processing is required as a magnet, and the process of setting the magnetization direction finely is omitted. There is also disclosed an electroacoustic transducer (Patent Document 4) with improved properties.

Japanese Patent Publication No. 35-10420 Japanese Utility Model Publication No. 60-93397 Patent No. 3612319 Patent No. 4810576 Japanese Patent Application Publication No. 2003-70093

In the electroacoustic transducers of (Patent Document 3) and (Patent Document 4), the combination of partial magnets can ensure a region with a high effective magnetic field strength in a very wide range, and adjust the effective magnetic field strength to make it uniform. It also became possible to do.
As a result, it becomes possible to use the entire surface as a conductor even with a voice coil diaphragm of a large area, and it has become possible to reproduce sounds with extremely excellent transient characteristics up to the low sound range. In addition, it was possible to increase the effective magnetic field strength and the efficiency.
With these features, it has become possible to adopt a voice coil diaphragm capable of driving the entire surface of the vibration plane in the same phase over the entire range from the low range to the high range. In speakers, headphones, etc., it is possible to realize an ideal full-drive flat speaker with low distortion and to convert an electrical signal into a sound of high quality. Microphones and the like have an excellent function of being able to convert sound into an electrical signal maintaining high quality.

(1) However, in the case of the structure adopted in the electroacoustic transducer of (patent documents 1 to 4), it is necessary to form a magnetic field in a wider space than the magnetic circuit of a general speaker such as a cone type, Since the magnetic field of the space due to the magnet plate is developed in three dimensions from the magnetic pole, the presence of the perpendicular magnetic field component can not be avoided. Further, although the magnetic field in space is divided into a parallel magnetic field component and a vertical magnetic field component, only a parallel magnetic field component can be used with a planar voice coil diaphragm.
Therefore, in the region of the conductor of the voice coil diaphragm, most of the parallel magnetic field component contributes as an effective magnetic field component and is used for driving the conductor (vibration of the voice coil diaphragm). The magnetic field component has not yet been utilized to drive the conductor.
Further, in a region where the proportion of the perpendicular magnetic field component is large even if the magnetic field strength is high, the proportion of the parallel magnetic field component is small and the effective magnetic field strength is low, so the voice coil diaphragm can not be installed. As described above, although the magnetic field strength is high, a large proportion of the perpendicular magnetic field component still leaves many regions which are not used for the vibration of the voice coil diaphragm. In particular, in the disk-shaped magnet plate employed in (Patent Document 3) and (Patent Document 4), the proportion of the perpendicular magnetic field component is large despite the fact that the magnetic field strength at the central part is very high. The magnetic field could not be used effectively.
(2) Generally, when the frequency of the sound generated by the vibration of the diaphragm increases, the sound pressure decreases as the angle to the vibration direction increases even if the distance from the diaphragm is the same, ie, the directivity Deterioration of the characteristics occurs.
In the case of the electroacoustic transducer using the voice coil diaphragm until now like (patent documents 1-4), the vibration direction of the voice coil diaphragm was only the center axis direction of the electroacoustic transducer. In the directivity characteristic, the sound pressure decreases as the angle with respect to the central axis which is also the vibration direction increases, so if the vibration direction itself is dispersed to other than the central axis, the effect of preventing the sound pressure drop can be expected in directions other than the central axis.
Since the vibration of the conductor driven by the perpendicular magnetic field component is parallel to the surface of the magnet plate, if the voice coil diaphragm can utilize not only the parallel magnetic field component but also the perpendicular magnetic field component, the voice coil diaphragm Can be vibrated in many directions, and there is a possibility that the directivity characteristic can be greatly improved.
(3) The coaxial speaker is an ideal multi-way speaker, but as described in the third embodiment of (Patent Document 4), the high-range speaker is coaxial with the center of the low-range speaker In such a case, it was necessary to incorporate a dedicated magnetic circuit for the high frequency range speaker. As a result, new magnets are needed for the magnetic circuit of high-range speakers, and the complicated process of incorporating these magnets into parts has also increased. In particular, the components of the high-range speaker are small, and if a dedicated magnetic circuit is newly provided in the center, the structure becomes complicated and the integration becomes considerably difficult.
In the disk-shaped magnet plate employed in (Patent Document 3) and (Patent Document 4), the magnetic field strength of the central portion not used is considerably higher than the effective magnetic field strength in the voice coil diaphragm. However, since the magnetic field at the central portion has a large proportion of the perpendicular magnetic field component and low effective magnetic field strength, it can not be used to drive the conductor. Therefore, if the perpendicular magnetic field component can be used to drive the conductor, the high-range voice coil diaphragm can be installed without newly providing a magnet for the high-range speaker. Thus, the use of the perpendicular magnetic field component was considered to be an effective means for enabling the high frequency range speaker to be easily coaxially installed.
(4) As described in the third embodiment of (Patent Document 4), when the high range speaker is coaxially disposed at the center of the low range speaker, the magnet plate of the high range speaker is low. When entering the area of the range speaker, the size on the inner diameter side of the low frequency range voice coil diaphragm was affected. In the case of a large-bore speaker with a large aperture, there is no problem even if the treble-range speaker is coaxially installed since the region not used for driving the central portion is large, but if the aperture is smaller, the central portion The area that was not used for driving was reduced, and the influence was increased. Small diameter coaxial two-way speaker units have been highly desirable because they can be relatively inexpensive to construct high performance speaker systems that can be adapted to a variety of applications. However, for the reason described above, it was difficult to adopt a structure in which the high-range speakers are coaxially arranged with a small-diameter speaker.
Therefore, if it becomes possible to use the perpendicular magnetic field component for driving the conductor, the magnet can be installed only with the high-range voice coil diaphragm without providing a new magnet for the high-range speaker. However, it will be possible to adopt a structure in which high frequency range speakers are coaxially arranged.
From the above point of view, in order to design a better speaker than before, not only generality and improvement of utilization efficiency of magnet but also application to performance of the directivity characteristic and coaxial type speaker, vertical magnetic field component There has been a strong demand for development of an electroacoustic transducer used for driving a conductor.

The present invention meets the above-mentioned needs, and by utilizing not only the parallel magnetic field component of the magnetic field formed by the magnet plate but also the vertical magnetic field component in the electroacoustic transducer adopting the voice coil diaphragm, a new vibration form is realized. The goal is to achieve higher performance and diversification of electroacoustic transducers.
By using the perpendicular magnetic field component to drive the conductor, a loudspeaker with excellent magnet utilization efficiency and extremely good directional characteristics is realized, and this coaxial speaker is considered to be an ideal multi-way speaker. It is intended to install a range speaker without providing a dedicated magnetic circuit, thereby achieving downsizing of the entire size and adapting it to various usage forms.
The present invention is a speaker, headphone, earphone, etc. that can efficiently convert an electrical signal to sound which is excellent in sound quality, versatility, mass productivity and resource saving, in addition to the improvement to the above-mentioned demand. It is an object of the present invention to provide an electroacoustic transducer such as a microphone and a sound wave sensor that can efficiently perform conversion to

In order to solve the above-mentioned subject, the electroacoustic transducer of the present invention has the following composition.
An electro-acoustic transducer according to claim 1 of the present invention includes a magnet plate, and a coil vibrator that is formed by winding a conductor and is disposed in front of the magnet plate, (a) The coil vibrator is vibrated to generate a sound by an electromagnetic force generated by a magnetic field formed by the magnet plate and an acoustic signal current flowing through the conductor of the coil vibrator, or (b) the magnet plate An electro-acoustic transducer that generates an acoustic signal current in the conductor of the coil vibrating body by the magnetic field formed by and the vibration of the coil vibrating body due to sound, wherein the coil vibrating body is the magnet plate A vibrating surface inclined with respect to the front surface of the magnet plate, or a vibrating surface perpendicular to the front surface of the magnet plate, wherein the vibrating surface is formed in a loop shape, and the vibration of the coil vibrating body is at least Having a component parallel to the front surface It is equipped with a.
This configuration has the following effects.
(1) The coil vibrating body has a vibrating surface inclined with respect to the front surface of the magnet plate or a vibrating surface perpendicular to the front surface of the magnet plate, and the vibrating surface is formed in a loop shape. By vibrating the vibrating surface so as to expand and contract in a direction close to perpendicular to the vibrating surface, the vibration of the coil vibrating body has a component parallel to the front surface of the magnet plate. Thereby, the magnetic field formed by the magnet plate is not only a parallel magnetic field component parallel to the front surface of the magnet plate, but also a perpendicular magnetic field component perpendicular to the front surface of the magnet plate from electrical signal to sound or from sound to electrical signal It can be used effectively for conversion to In this way, the utilization efficiency of the magnet can be improved, and a new form of vibration with many possibilities allows different structures to be adopted.
(2) Since the composite of the parallel magnetic field component and the perpendicular magnetic field component of the magnetic field formed by the magnet plate can be used as an effective magnetic field component, the vibration of the coil vibrator is only in the direction perpendicular to the surface of the magnet plate It can be made to have vibration not only in parallel direction but also in parallel direction. If the vibration of the coil vibrator can be made to be a vibration having a component in a direction parallel to the surface of the magnet plate, the coil vibrator can be vibrated in many directions. Therefore, the sound pressure in the direction deviated from the central axis direction of the electroacoustic transducer, as compared with the cone-type speaker in which the vibration direction of the diaphragm is only the central axis direction or the conventional electroacoustic transducer using a voice coil diaphragm. The directivity can be greatly improved by reducing the decrease.
(3) The central portion of the magnet plate employed in (Patent Document 3) and (Patent Document 4) has a large perpendicular magnetic field component, so the coil vibrator of the present invention is coaxially disposed in the central portion for high frequency range By utilizing as a speaker, very high effective magnetic field strength can be obtained. In addition, since this method can operate the coil vibrator without providing a magnetic circuit dedicated to the high-range speaker, space can be saved and the size of the coaxial speaker can be made smaller than before. . As described above, by adopting the coil vibrator of the present invention for the high frequency range speaker of the coaxial type speaker, the structure can be simplified, and it is extremely effective in reduction of parts and man-hours and performance improvement such as directivity characteristics. Big effect can be obtained.
(4) Since a combination of the parallel magnetic field component and the perpendicular magnetic field component of the magnetic field formed by the magnet plate can be used as an effective magnetic field component, only by increasing the effective magnetic field strength of the region used so far However, the effective magnetic field strength is increased even in the region which has not been available until now, and a newly available region is generated. In addition, by adjusting the shape of the coil vibrator in accordance with the magnetic field distribution, the inclination of the vibration plane of the coil vibrator can be adjusted to increase the effective magnetic field strength, so the restriction on the magnetic field distribution is reduced. Since the freedom in design of a magnet board increases by these things, the design range can be expanded and the structure of a magnet board can be simplified, and it came to be excellent in design freedom and mass productivity.

Here, the coil vibrator is formed by winding a conductor made of aluminum, copper, copper clad aluminum wire, silver, gold or the like into a thin plate shape so as to have a predetermined shape, or by bending after winding. The shape of the Bonding between conductors can be performed using silicone resin, epoxy resin, synthetic resin adhesive such as cyanoacrylate, etc., but use means such as soldering or wire bonding for parts where there is no need for insulation. Can.
In the case of winding and using a linear conductor, a plurality of wires are wound in parallel and adjusted to have a predetermined impedance. An insulated conductor may be used, but in the case of using an uninsulated conductor, the conductor groups in parallel are insulated and wound.
In addition, a conductor such as aluminum, copper, silver, gold or the like on the surface of a thin substrate made of synthetic resin or ceramic such as polyimide, polyethylene or polycarbonate which is nonmagnetic material, ceramic, synthetic fiber, wood fiber or composite material thereof It is also possible to use one in which the pattern is formed into a predetermined shape by etching means, evaporation means, plating means or the like, or one in which a conductor portion is formed and then bent to form a predetermined shape.
Furthermore, as a method of forming a pattern of a conductor, there is a method of cutting a thin conductive plate of copper, aluminum or the like using a method such as pressing with a mold or laser processing.
In addition, as described in various conventional patent documents, the above-mentioned means and processing method can be made to meet the purpose more by using a combination of a plurality rather than using each of them alone. There are many.

The shape of the coil vibrator has a vibrating surface inclined or perpendicular to the front surface of the magnet plate, and the vibrating surface is formed in a loop shape.
The point that the vibration of the coil vibrator has a vibration component parallel to the front surface of the magnet plate is a feature that is largely different from the prior art. That is, it is not a flat shape like a conventional voice coil diaphragm, but forms a loop in which an inclined surface or a vertical surface is closed and has a three-dimensional shape, so it is parallel to the front surface of the magnet plate. Is also able to vibrate.
In particular, by arranging a recess (valley fold) or a protrusion (crest fold) in the circumferential direction of the vibrating surface and curving the top, the vibration surface is a recess (valley fold) or a convex (crest fold) ) Has a structure to elastically support each other, and it becomes easy to vibrate in the inward direction and outward direction (radial direction) of the loop, so it has at least two recesses (valley folds) or projections (peak folds) Is preferred. As a result, the cross section of the coil vibrator can be formed in various shapes, but in the case of a circular shape, the magnetic field acts in axial symmetry and does not expand and contract in the radial direction, which is not preferable.
Incidentally, even if it is circular, if it is formed in a loop while providing small irregularities on the vibration surface, it can be expanded and contracted in the radial direction by elastic deformation of the irregularities, so that sound is easily generated.
In this state, the electromagnetic force generated by the perpendicular magnetic field component and the acoustic signal current works so that the vibration surface of the coil vibrator vibrates inward or outward of the loop, so it can contribute to the generation of sound and the perpendicular magnetic field component It can contribute to the effective magnetic field component.
The shape of the coil vibrator may be enlarged or reduced in diameter toward the front of the magnet plate, and it functions effectively even if the vibrating surface is perpendicular to the front surface of the magnet plate. When installing a coil vibrator with a diameter-expanded or diameter-reduced shape, the side facing the front of the magnet plate is difficult to emit sound to the outside, and the opposite side is used as the front side. Is good. Therefore, when the diameter of the coil oscillator is expanded toward the front of the magnet plate, sound is emitted from the surface of the coil oscillator toward the inside of the loop, and when the diameter is reduced, the surface of the coil oscillator is reduced. Sound is emitted from the outside of the loop.

In the conductor of the coil vibrator, an electromagnetic force proportional to the parallel magnetic field component is generated in a direction perpendicular to the front surface of the magnet plate, and an electromagnetic force proportional to the vertical magnetic field component in the direction parallel to the front surface of the magnet plate Force is generated. The coil vibrator vibrates due to this electromagnetic force, but the direction of the vibration does not necessarily coincide with the direction of the generated electromagnetic force because it is influenced by the surrounding vibration and the support portion.
In the vibration generated in the coil vibrator, a vibration component perpendicular to the vibration surface can be effectively used for converting an electric signal into sound. Therefore, in the coil vibrator having a vibrating surface perpendicular to the front surface of the magnet plate, only the vibration component parallel to the front surface of the magnet plate can be effectively used for converting the electric signal into sound.
The coil vibrator is placed so that the effective magnetic field strength is higher with respect to the conductor forming the vibrating surface, so that the efficiency of conversion from electric signal to sound or conversion from sound to electric signal is high. Also, the utilization efficiency of the magnet can be enhanced.
For that purpose, it is preferable to place the vibrating surface formed of a conductor at a position and an angle so as to increase the effective magnetic field strength. That is, the coil vibrator is disposed at a position where the magnetic field strength is high, the vibration plane formed of the conductor is parallel to the direction of the magnetic field, and the acoustic signal current flowing in the conductor is perpendicular to the direction of the magnetic field. It is ideal to be in the cross direction. In that case, the direction of the electromagnetic force is perpendicular to the vibration plane of the coil vibrator.
Further, the efficiency can be increased by increasing the total area of the vibration surface of the coil vibrator.

The invention according to claim 2 is the electro-acoustic transducer according to claim 1, wherein the vibration surface of the coil vibrator is formed in a loop shape while repeating unevenness.
According to this configuration, in addition to the actions and effects of claim 1, the following actions and effects are obtained.
(1) The vibrating surface of the coil vibrator is formed in a loop shape while repeating unevenness, so that the vibrating surfaces are elastically supported each other, and expand and contract in the inward direction and outward direction (radial direction) of the loop. It becomes easy to vibrate. Therefore, the influence of the vibration at each position of the coil vibrator on each other is reduced, and a uniform and stable vibration can be obtained. As a result, irregular vibration is less likely to occur, and frequency characteristics are easily made uniform.
(2) The efficiency can be increased as the total area of the conductor portion of the coil vibrator is increased, but generally, when the outer diameter of the diaphragm is increased, the directivity characteristic is deteriorated in the reproduction of the high frequency range. However, in the present invention, by forming the vibration surface of the coil vibration member in a loop while repeating asperity, the total area of the vibration surface of the coil vibration member is increased with an outer diameter equal to that of the conventional flat voice coil diaphragm. it can. Therefore, even if the area of the coil vibrator is increased in order to enhance the efficiency, the outer diameter does not increase and deterioration of the directivity can be prevented.
(3) In addition, since the outer diameter can be reduced while maintaining the total area of the vibration plane equivalent to that of the conventional flat voice coil diaphragm, the outer diameter can be reduced while maintaining the efficiency. You can make improvements. Furthermore, by reducing the outside diameter to make it compact, space saving is also possible, and it is excellent in the ease of installation, and in particular, as the high frequency range speaker coaxially arranged in the center of the low frequency range speaker High quality, high performance can be realized.

Here, the vibration surface of the coil vibrator is formed in a loop while repeating unevenness, but the shape thereof is such that each position of the coil vibrator can vibrate according to the electromagnetic force, and the coil vibration of the present invention As an electroacoustic transducer using a body, it is determined in consideration of high conversion efficiency (efficiency) to sound energy.
In order to allow each position of the coil vibrator to vibrate according to the electromagnetic force, the coil vibrator is easily deformed when it vibrates. Further, since the coil vibrators are elastically supported, the vibrations generated at the respective positions of the vibrators do not influence each other. For this purpose, it is necessary to provide a large number of asperities on the vibrating surface and to distribute them uniformly.
Next, in order to increase the efficiency, the coil vibrator should be shaped to efficiently generate sound as described below, and the generated sound should be shaped to be emitted to the outside efficiently. is important.

First, the shape of the coil vibrator capable of efficiently generating sound will be described.
Sound can be generated efficiently by making the vibrating surface formed of a conductor inclined such that the effective magnetic field strength is the highest. In general, the inclination that makes the effective magnetic field strength highest is parallel to the direction of the magnetic field, with the vibrating surface of the coil vibrator formed of the conductor parallel to the direction of the magnetic field. The inclination is orthogonal to the other.
The coil vibrator has a plurality of bent portions, and the shape of the entire coil vibrator is often complicated, and the effective magnetic field strength is highest at all of the vibration planes formed of the conductor. It is difficult. Therefore, it is preferable to set the direction of the vibration plane to an angle such that the effective magnetic field strength is generally increased.
Generally, in order to obtain the highest efficiency with respect to the central axis direction, ie, the direction perpendicular to the front surface of the magnet plate at the center of the magnet plate, the inclination angle of the vibrating surface with respect to the front surface of the magnet plate is The angle is 70 degrees to 20 degrees, preferably about 60 degrees to 30 degrees.
In the direction of the magnetic field in such a range, a high magnetic field strength is easily obtained, and since the range is set to a certain degree, the change in the vibration direction is reduced and a stable vibration is easily obtained.
As the inclination angle of the vibrating surface with respect to the front surface of the magnet plate becomes larger than 60 degrees, the parallel component of the vibration of the coil vibrating member becomes large, and tends to contribute efficiently to the central axis direction at high frequency . Also, as the inclination angle of the vibrating surface with respect to the front surface of the magnet plate becomes smaller than 30 degrees, it tends to be difficult to obtain high magnetic field strength. Furthermore, when the inclination angle of the vibrating surface with respect to the front surface of the magnet plate is larger than 70 degrees or smaller than 20 degrees, these tendencies become remarkable, which is not preferable.
The distribution of the magnetic field suitable for the vibration plane having a large inclination angle can be obtained relatively easily, and the magnetic field intensity also tends to be high. Therefore, it is effective to adopt a vibrating surface with an angle of 70 degrees or more with respect to the front surface of the magnet plate by a device such as using with a diffuser.

Next, the shape in which the generated sound is efficiently emitted to the outside will be described.
In order to efficiently emit the generated sound to the outside, it is necessary to prevent the recess from becoming deep in the uneven portion.
In addition, when the diameter of the coil vibrator is expanded toward the front of the magnet plate, sound is emitted from the surface of the coil vibrator toward the inside of the loop, but it is deeper when the height of the coil vibrator is increased. Generally, it is preferable that the height of the coil vibrator is low, since it is difficult to release the sound of the position to the outside. Furthermore, the smaller the inclination angle of the vibrating surface, the easier the sound is emitted to the outside.
When the diameter of the coil vibrating body is expanded toward the front of the magnet plate, the coil vibrating body itself becomes close to the shape of the horn, so that the feature of the horn type speaker is also shown. When the characteristics of the horn type speaker are actively used, the condition of the horn design is followed, and in this case, the height of the coil vibrator may be increased.
As described above, since there are contradictory conditions, the shape of the coil vibrator is generally determined in accordance with the purpose based on each of these conditions.

By constructing the magnet plate by means proposed in (Patent Document 3) and (Patent Document 4) as the magnet plate under the conditions as described above, high effective magnetic field strength can be obtained also in the present invention. That is, it is most preferable to divide the entire magnet plate into a plurality of partial regions, and to make each partial region a magnetization direction for increasing the usage efficiency of the magnet.
A magnet plate incorporating a cylindrical magnet whose magnetization direction is perpendicular to the central hole of the cylindrical magnet whose magnetization direction is the radial direction can relatively easily obtain high effective magnetic field strength.
In general, in the case of a cylindrical magnet, the direction of the magnetic field with respect to one end face of the magnetic pole is almost in the range of about 90 degrees to about 30 degrees in the portion where the magnetic field strength is high. Therefore, simply setting the coil vibrator of the present invention in front of one of the magnetic poles of the cylindrical magnet reduces the efficiency but can be easily used as an electroacoustic transducer.
As described above, the coil vibrator of the present invention also has the versatility of being easily adaptable to various magnet plates.

The invention according to claim 3 is the electro-acoustic transducer according to claim 1 or 2, which has a configuration including a plurality of coil vibrators.
According to this configuration, in addition to the actions and effects of claim 1 or 2, the following actions and effects are obtained.
(1) The coil vibrator is complicated in its overall shape and difficult to manufacture if a plurality of bent portions are provided, but the shape can be easily realized by dividing and combining the plurality of coil vibrators. Become.
(2) A complex shape can be easily realized when divided into a plurality of coil vibrators, so it is easy to adjust the inclination of the vibrating surface formed of a conductor. Therefore, it is easy to adjust the inclination of the vibrating surface to increase the effective magnetic field strength.
(3) Since the coil vibrator is divided into a plurality of parts, the loop of the coil vibrator is unlikely to be high in the forward direction of the magnet plate. Therefore, the conductor of the coil vibrator is distributed at a position close to the magnet plate, that is, at a position where the magnetic field strength is high, and the utilization efficiency of the magnet becomes high. In addition, even when the coil vibrator is expanded in the forward direction of the magnet plate, sound is easily emitted to the outside.
(4) It is possible to combine the coil vibrators whose diameter is expanded toward the front of the magnet plate and the coil vibrators whose diameter is reduced, and it is also possible to use different inclinations and shapes of the vibration surface for each coil vibrators. Fine adjustment of characteristics and directivity characteristics.

According to the electroacoustic transducer of the present invention, the following advantageous effects are obtained.
According to the first aspect of the present invention, the following effects can be obtained.
(1) A vibrating surface inclined with respect to the front surface of the magnet plate of the coil vibrator or a vibrating surface perpendicular to the front surface of the magnetic plate vibrates so as to expand and contract in a direction close to perpendicular to the vibrating surface. The vibration of the coil vibrator will have a component parallel to the front of the magnet plate. If the vibration of the coil vibrator also has a component in the parallel direction with respect to the plane of the magnet plate, the coil vibrator can be vibrated in many directions. Thereby, the utilization efficiency of a magnet can be improved and it comes to be excellent in design freedom. Moreover, since the sound pressure drop in the direction away from the central axis direction can be reduced, it is possible to provide an excellent electroacoustic transducer having extremely good directivity.

According to the second aspect of the invention, in addition to the effects of the first aspect, the following effects are obtained.
(1) The vibration surfaces of the coil vibrators elastically support each other, and it is easy to vibrate so as to expand and contract in the inward direction and the outward direction (radial direction) of the loop. Therefore, the influence of the vibration at each position of the coil vibrator on each other is reduced, and a uniform and stable vibration can be obtained. In this way, it is possible to provide an electroacoustic transducer having uniform frequency characteristics in which random vibration is less likely to occur.

According to the third aspect of the invention, in addition to the effects of the first or second aspect, the following effects are obtained.
(1) It is possible to provide an electroacoustic transducer which can easily realize the shape of a coil vibrator having a complicated shape by combining the plurality of coil vibrators separately.

Principal part cross-sectional schematic end view of the electro-acoustic transducer in the first embodiment Principal part schematic plan view of the electroacoustic transducer in the first embodiment FIG. 12 is a schematic perspective view of a main part showing the outer shape of the coil vibrating body of the electroacoustic transducer according to the first embodiment. Principal part cross-sectional schematic end view of an electroacoustic transducer in Embodiment 2 Principal part schematic plan view of the electroacoustic transducer in the second embodiment Principal part cross-sectional schematic end view of intermediate portion in height direction of coil vibrator of electro-acoustic transducer in Embodiment 3. Principal part cross-sectional schematic end view of height direction intermediate part of coil vibrating body showing a first modification of the electroacoustic transducer according to the third embodiment A sectional view of an essential part of a height direction intermediate part of a coil vibrator showing a second modification of the electroacoustic transducer according to the third embodiment. FIG. 3 is a cross-sectional schematic end view of an essential part of a height direction intermediate part of a coil vibrator showing a third modification of the electroacoustic transducer in the third embodiment. FIG. 14 is a cross-sectional schematic end view of a main part in the height direction intermediate part of the coil vibrator, showing a fourth modification of the electroacoustic transducer in the third embodiment

Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings. The technical scope of the present invention is not limited to these embodiments.
Embodiment 1
The electroacoustic transducer in Embodiment 1 will be described.
FIG. 1 is a cross-sectional schematic end view of the main part of the electro-acoustic transducer in the first embodiment, FIG. 2 is a main part schematic plan view of the electro-acoustic transducer in the first embodiment, and FIG. It is a principal part model perspective view showing the outline of the coil vibrator of an electroacoustic transducer in a.
In FIG. 1 and FIG. 2, 10 is an electroacoustic transducer of Embodiment 1 by which the coil vibration body 30 is arrange | positioned ahead of the magnet board 20 mentioned later.
First, the magnet plate used for the electroacoustic transducer of Embodiment 1 will be described.
In FIG. 1, 20 is a magnet plate of the electro-acoustic transducer 10 which is generally formed in a substantially disk shape, 21 is a central region magnet using a cylindrical neodymium magnet in a partial region on the center side of the magnet plate 20, and 21a is A bolt insertion hole provided at the center of the central area magnet 21; 22 is a partial area around the magnet plate 20; a plurality of trapezoidal small magnets 22b using neodymium magnets are radially emitted around the central area magnet 21 It is a basic area magnet arranged and configured.
Further, in FIG. 2, reference numeral 22 a denotes a plurality of sound passing holes formed between trapezoidal small magnets 22 b adjacent to each other in the basic area magnet 22.

  In FIG. 1, the cylindrical central area magnet 21 is magnetized in the axial direction of the magnet plate 20. Further, the basic area magnet 22 is magnetized in the radial direction. Although the basic area magnet 22 is configured by combining a plurality of trapezoidal small magnets 22 b in the present embodiment, a single cylindrical magnet magnetized in the radial direction may be used as the basic area magnet 22. The sound passage hole is not necessarily provided, but instead of the sound passage hole 22a, a gap may be provided between the central area magnet 21 and the basic region magnet 22 and used as a sound passage hole.

Next, the details of the coil vibrator used in the electroacoustic transducer according to the first embodiment will be described.
In FIG. 1, reference numeral 31 denotes a conductor wound in a spiral shape to form a coil vibrating body 30, and 33 denotes a vibrating surface of the coil vibrating body 30 inclined with respect to the front surface of the magnet plate 20. The inclination angle of the vibration surface 33 of the coil vibrating body 30 can be appropriately selected according to the direction of the magnetic field formed by the magnet plate 20 in such a manner that the effective magnetic field strength generally increases. By setting the inclination angle of the vibrating surface 33 to 70 degrees to 20 degrees, preferably 60 degrees to 30 degrees with respect to the front surface, the magnetic field can be effectively used to increase efficiency, which is preferable.
As shown in FIG. 3, by alternately providing the mountain folds 33 x and the valley folds 33 y in the circumferential direction of the coil vibrator 30 and curving the tops, the vibration surface 33 is formed in a loop shape repeating unevenness. There is.
In order to form the coil vibrator 30 having a shape as shown in FIG. 3, first, the conductor 31 made of an insulated copper clad aluminum wire is spirally wound, an adhesive is applied and fixed to the back surface, and a thin ring is formed. Create a flat coil in the shape of a circle. Although various methods have been disclosed for the method of producing the planar coil, any method may be used as long as the planar coil can be formed.
Thereafter, the flat coil can be molded by pressing a flat coil or the like to a mold or the like formed in the same shape as the coil vibrator 30 shown in FIG.
Once the planar coil is manufactured, this method of forming the coil vibrator 30 by molding is easy to manufacture, but the inclination angle of the vibration surface 33 is limited to some extent. In order to make the coil vibrator 30 into an ideal shape, after determining the shape that has the highest effective magnetic field strength and that the sound is likely to be emitted, the shape is made by winding, evaporation, plating, etc. It is good to adopt the method of making it together directly.

The structure of the electroacoustic transducer 10 using the magnet board 20 and the coil vibrating body 30 which were comprised as mentioned above is demonstrated.
In FIG. 1, reference numeral 40 denotes a nonmagnetic cylindrical frame that surrounds the outer periphery of the coil oscillator 30, and 40a is a nonmagnetic material formed in a disk shape and has an opening 40b that matches the shape of the outer periphery of the coil oscillator 30. A front support frame for supporting the outer peripheral side of the coil vibrating body 30 together with the cylindrical frame 40, 41 is a silicone resin and coil vibration while sealing between the unevenness on the inner peripheral edge side of the coil vibrating body 30 and the central area magnet 21 An inner peripheral support portion elastically supporting the inner peripheral side of the body 30, and 42 is filled so as to seal between the unevenness on the outer peripheral edge side of the coil vibrating body 30 and the cylindrical frame 40 and the front support frame 40a. An outer peripheral support portion elastically supporting the outer peripheral side of the coil vibrating body 30 with silicone resin, 45 is filled in a space surrounded by the back surface of the coil vibrating body 30, the inner peripheral surface of the cylindrical frame 40 and the magnet plate 20 glass A sound absorbing material 51 using a ring or the like, an outer peripheral frame 51 formed of a nonmagnetic material in a cylindrical shape and installed on the outer peripheral side of the basic region magnet 22, 52 a ring shape of a nonmagnetic material, the basic region magnet 22 An intermediate frame of the electroacoustic transducer 10 supported at the front, 53 is a ring formed of nonmagnetic material, a central frame installed in front of the central area magnet 21, 53a is a bolt insertion hole provided at the center of the central frame 53 , 54 is a nonmagnetic body formed in a ring shape and supports the magnet plate 20 at the rear, the rear frame of the electroacoustic transducer 10, 54a is a bolt insertion hole provided at the center of the rear frame 54, 54b is an opening in the rear frame 54 A plurality of sound passing holes provided by forming a part, 56 is a nonmagnetic material penetrating the central frame 53, the bolt insertion hole 21a of the central area magnet 21 and the bolt insertion hole 54a of the rear frame 54 Ltd. bolts 57 center frame 53 is screwed to the bolt 56 in the rear surface of the rear frame 54, the magnet plate 20, which is a non-magnetic material made of a nut fixedly connecting the rear frame 54.
The arrows indicate the direction of the magnetic field formed by the magnet plate 20.

  In FIG. 1, since the magnetic force pushing the central region magnet 21 forward by the basic region magnet 22 acts on the central region magnet 21, there is a possibility that the adhesive may be detached only when fixed to the rear frame 54. Therefore, the central area magnet 21 is fixed by being sandwiched between the central frame 53 and the rear frame 54 using bolts 56 and nuts 57. In addition, since the magnetic force acts on the basic area magnet 22 in the direction to press it against the rear frame 54 by the central area magnet 21, it is difficult to remove just by bonding, but the multiple small magnets 22 b in combination are difficult to disassemble A cylindrical outer peripheral frame 51 is provided on the

The direction of the magnetic field formed by the magnet plate 20 in the electro-acoustic transducer 10 of the present embodiment is as shown by the arrows in FIG. 1. However, when current flows through the conductor 31 of the coil vibrator 30, the coil vibrator 30 The electromagnetic force acts in a direction perpendicular to both the direction of the magnetic field and the direction of current flow. That is, the electromagnetic force works in a direction close to perpendicular to the vibration surface 33 of the coil vibrator 30. As a result, the coil vibrating body 30 operates alternately in the contracting direction and the expanding direction to vibrate and generate sound. The coil vibrator 30 itself generates a sound by deformation and vibration, so the inner support portion 41 supporting the inner peripheral side of the coil vibrator 30 and the outer support supporting the outer peripheral side of the coil vibrator 30 It is preferable to use an elastic material such as silicone resin for the part 42.
In addition, since the sound on the rear surface side of the coil vibrating body 30 interferes with the sound on the front surface side of the coil vibrating body 30, it is necessary to reduce the leakage to the outside as much as possible. Therefore, in order to attenuate the sound on the rear surface side of the coil vibrating body 30, the sound absorbing material 45 is installed in the space surrounded by the rear surface of the coil vibrating body 30, the inner peripheral surface of the cylindrical frame 40 and the magnet plate 20.
The sound having passed through the sound absorbing material 45 is made to reach the sound passage hole 22a (FIG. 2), and when a space behind the coil vibrating body 30 is further required, the electroacoustic wave from the sound passage hole 54b (FIG. 1) It is made to be able to emit outside the converter 10. In such a case, it is possible to select to pack the sound absorbing material in the sound passage hole 22a or to increase the size of the sound passage hole 22a depending on the situation. Furthermore, a sound passage hole may be provided in the outer peripheral frame 51 and released to the outside of the electroacoustic transducer 10.
If the space behind the coil vibrating body 30 may be small, the space between the rear of the cylindrical frame 40 and the inner peripheral side support portion 41 is sealed, and the sound on the rear surface side of the coil vibrating body 30 is It may be shut off at a stage before reaching the sound passage hole 22a.

The utilization efficiency of the magnetic field formed by the magnet plate 20 becomes higher as the direction of the magnetic field and the vibration surface 33 of the coil vibrator 30 are closer to parallel, and as the winding direction of the conductor 31 and the direction of magnetic field are closer to perpendicular .
Therefore, when forming the coil vibrating body 30, the winding direction of the conductor 31 and the direction of the magnetic field are made so that the vibrating surface 33 becomes close to parallel to the direction of the magnetic field in the widest possible area of the coil vibrating body 30. It is preferable to design the shape, the number, the arrangement, and the like of the mountain fold 33x and the valley fold 33y such that the height of the ridge 33x is close to perpendicular.
Lead wires (not shown) are drawn out from the inner peripheral side and the outer peripheral side of the spirally wound conductor 31 of the coil vibrator 30, and are connected to terminals (not shown). When using the electroacoustic transducer 10 as a speaker, headphones, etc., a drive current can be supplied from the outside from a terminal.
When the electroacoustic transducer 10 is used as a microphone or the like, the coil vibrator 30 is vibrated by sound, and an electromotive force generated in the conductor 31 is extracted as an electrical signal from a terminal to which the lead wire is connected.

In the present embodiment, the magnet plate 20 is configured by combining two types of magnets, the central region magnet 21 and the basic region magnet 22, but the configuration of the magnet plate 20 is not limited to this, and may be selected appropriately. be able to. For example, when the magnet plate is configured with only cylindrical magnets magnetized in the axial direction, the output sound pressure level decreases, but the amount of use of the magnet can be reduced, and the configuration of the magnet plate is simplified and electricity is used. It is possible to miniaturize the acoustic transducer.
Further, in the present embodiment, the case where the coil vibrating body 30 is used alone has been described. However, the high frequency range speaker as described in the third embodiment of (Patent Document 4) is a low frequency range speaker In the composite type speaker coaxially arranged at the central portion, by adopting the coil vibrating body 30 as the high frequency range speaker, the magnet portion for the high frequency range speaker provided exclusively is not necessary. That is, a high-performance coaxial composite speaker is configured simply by configuring a non-coaxial bass speaker and disposing the coil vibrating body 30 surrounded by the tubular frame 40 as it is in the central portion as a high-range loudspeaker. it can. In such a case, it may be better to change the size of the partial magnet at the central portion in order to increase the efficiency of the high-range speaker, but the type of magnet and the basic structure need not be changed.

According to the electroacoustic transducer of the first embodiment configured as described above, the following operation can be obtained.
(1) The coil vibrator has a vibrating surface inclined with respect to the front surface of the magnet plate, and the vibrating surface is formed in a loop shape, so that the vibrating surface of the coil vibrator is perpendicular to the front surface of the magnet plate In addition to the direction (axial direction), it is possible to vibrate so as to expand and contract in a direction (radial direction = inward direction and outward direction of loop) parallel to the front surface of the magnet plate. Therefore, not only a parallel magnetic field component parallel to the front surface of the magnet plate but also a vertical magnetic field component perpendicular to the front surface of the magnet plate can be effectively used as the magnetic field formed by the magnet plate. Thus, the effective magnetic field strength can be increased to improve the utilization efficiency of the magnet.
(2) Since the perpendicular magnetic field component perpendicular to the front surface of the magnet plate can be used, the vibration component parallel to the front surface of the magnet plate can be generated by the vibration of the coil vibrator due to the perpendicular magnetic field component The Since this vibration component is in a direction parallel to the front of the magnet plate, the sound pressure drop in the direction away from the central axis direction of the speaker can be reduced and the directivity characteristic can be greatly improved. Especially as a high frequency range speaker Further high performance can be realized. In addition, the outer diameter can be reduced with an area equivalent to that of a conventional flat voice coil diaphragm by forming the vibration surface of the coil vibrator in a loop shape while repeating unevenness, and in reproduction of high-pitched area The directional characteristics are improved. As described above, according to the coil vibrator of the present invention, it is possible to realize an excellent speaker whose directivity characteristics are significantly improved.
(3) When the coil vibrator is adopted as a high frequency range speaker of a coaxial composite type speaker, a magnet portion dedicated to the high frequency range speaker becomes unnecessary. Since the magnet part space for high frequency range speakers is not required, a coaxial composite speaker can be configured even with a small diameter speaker, and the structure of the magnet part is also simplified and the manufacture is very easy. Become. The coaxial speaker is an ideal multi-way speaker, but in this way it is possible to construct a high-performance composite speaker that can be miniaturized and is extremely excellent in directional characteristics.
(4) Since a combination of the parallel magnetic field component and the vertical magnetic field component of the magnetic field formed by the magnet plate can be used as an effective magnetic field component, the coil vibration member has low effective magnetic field strength only with the conventional parallel magnetic field component. By combining with the perpendicular magnetic field component even in the region which can not be used for the vibration of the above, it is possible to increase the effective magnetic field strength and expand the region which can be used for the vibration of the coil vibrator. Furthermore, since the range of utilization of the magnetic field distribution is expanded, the design range of the magnet plate can be expanded to simplify the structure of the magnet plate, which is excellent in design freedom and mass productivity.
(5) Since the vibration surface of the coil vibrator is formed in a loop while repeating unevenness, the vibration surfaces elastically support each other and expand and contract in an inward direction and an outward direction (radial direction) of the loop. It becomes easy to vibrate. As a result, the influence of vibration at each position on each other is reduced, and uniform and stable vibration can be obtained, and an electro-acoustic transducer having uniform frequency characteristics and less occurrence of random vibration is provided. You will be able to

Second Embodiment
An electroacoustic transducer in Embodiment 2 will be described. The same components as those of the first embodiment are denoted by the same reference numerals and the description thereof will be omitted.
FIG. 4 is a cross-sectional schematic end view of the main part of the electro-acoustic transducer in the second embodiment, and FIG. 5 is a main part schematic plan view of the electro-acoustic transducer in the second embodiment.
In FIGS. 4 and 5, electro-acoustic transducer 10A in the second embodiment is different from that in the first embodiment in that three coil vibrators 30A to 30C are arranged concentrically in front of magnet plate 20. And the outer peripheral side of the coil vibrating body 30C and the basic area magnet 22 is surrounded by the common cylindrical frame 40A.
4A and 4B, reference numerals 33A to 33C denote vibration planes of the coil vibrators 30A to 30C inclined with respect to the front surface of the magnet plate 20. The coil vibrators 30A to 30C can be formed in the same manner as the coil vibrator 30 of the first embodiment except for the dimensions. However, although the coil vibrators 30B and 30C at the intermediate portion and the outer peripheral side have the vibrating surfaces 33B and 33C expanded in diameter toward the front of the magnet plate 20 in the same manner as the coil vibrator 30 of the first embodiment The coil vibrating body 30A on the side (center side) reduces the diameter of the vibrating surface 33A toward the front of the magnet plate 20.
In FIG. 4 and FIG. 5, 41A is made of silicone resin in a sheet shape and elastically supports the inner peripheral side of coil vibrating body 30A while sealing the concavo-convex portion on the inner peripheral side of coil vibrating body 30A. The outer supporting side 42A is formed of a silicone resin in a sheet shape and elastically supports the outer peripheral side of the coil vibrating body 30C while sealing between the unevenness on the outer peripheral edge side of the coil vibrating body 30C and the cylindrical frame 40A. The support portion 43A is formed of silicone resin, and seals the uneven portion between the outer peripheral edge side of the coil vibrating body 30A and the inner peripheral edge side of the coil vibrating body 30B while enclosing the outer peripheral side of the coil vibrating body 30A and the inner peripheral side of the coil vibrating body 30B. , And an intermediate support portion 44A bonded to the central area magnet 21 of the magnet plate 20, the sheet 44 is made of silicone resin, and the outer peripheral edge side of the coil vibrator 30B and the coil vibrator Intermediate support joined to the basic area magnet 22 of the magnet plate 20 by elastically supporting the outer peripheral side of the coil vibrating body 30B and the inner peripheral side of the coil vibrating body 30C while sealing the uneven portion between the inner peripheral side of 0C. It is a department.

In the electroacoustic transducer 10A of the present embodiment, the direction of the magnetic field formed by the magnet plate 20 is as shown by the arrows in FIG. 4. However, when current flows through the conductor 31 of the coil vibrators 30A to 30C, the coil vibration occurs. An electromagnetic force acts on the bodies 30A to 30C in a direction perpendicular to both the direction of the magnetic field and the direction of current flow. In general, when the electromagnetic force works and vibrates in the direction perpendicular to the vibrating surfaces 33A to 33C of the coil vibrators 30A to 30C, the utilization efficiency of the magnetic field is the highest.
In the magnet plate used in Embodiment 1 or 2, when the outer diameter of the magnet plate 20 is reduced or the magnet plate 20 is formed thin as in the present embodiment, the distance from the front surface of the magnet plate 20 However, the reduction rate of the magnetic field strength tends to be large. Therefore, in the present embodiment, by dividing the coil vibrator into three types of coil vibrators 30A to 30C, the heights of the respective coil vibrators 30A to 30C do not become high relative to the forward direction of the magnet plate 20. And the conductor 31 is disposed in the region where the magnetic field strength is high.

The coil vibrator vibrates by moving alternately in the contracting direction and the expanding direction of the whole to generate a sound, and therefore, the coil vibrator effectively functions even if its shape is expanded or contracted.
When a coil vibrator having a diameter-expanded or diameter-reduced shape is installed, the side facing the front surface of the magnet plate 20 is a back surface because sound is less likely to be emitted outside, and the opposite surface is used as the surface. Therefore, in the case of the coil vibrators 30B and 30C expanded in diameter toward the front of the magnet plate 20, a sound is emitted from the surface of the coil vibrators 30B and 30C toward the inside of the loop, and the diameter is reduced. In the case of the coil vibrator 30A, sound is emitted from the surface of the coil vibrator toward the outside of the loop.

When a plurality of coil vibrators 30A to 30C are arranged concentrically as in the present embodiment, the coil vibrators 30A to 30C can generate sound even if any of the coil vibrators 30A to 30C is expanded. However, in the present embodiment, the utilization efficiency of the magnetic field is enhanced by making use of each feature.
It is better to lower the height of the coil vibrator in order to avoid that the diameter is radiated toward the inside of the loop and the sound is less likely to be emitted to the outside. The inclination angle of the coil vibrator with respect to the magnet plate 20 should be small. Further, in the present embodiment, the direction of the magnetic field formed by the magnet plate 20 is such that the inclination angle with respect to the front surface of the magnet plate 20 decreases with distance from the center of the magnet plate 20. If the angle is reduced according to the angle, the utilization efficiency of the magnetic field will be higher. As described above, since the mutual conditions are met, the coil vibrators 30B and 30C on the intermediate portion and the outer peripheral side are used in a shape in which the diameter is enlarged.
Furthermore, the inclination angle of the vibrating surface 33C with respect to the front surface of the magnet plate 20 is smaller than the inclination angle of the vibrating surface 33B of the coil vibrating body 30B in the middle. This is done in order to make the inclination of the vibrating surface close to the direction of the magnetic field to increase the effective magnetic field strength and to make the sound easy to be emitted outside.

There is no limitation as in the case of the expanded coil vibrator since the sound of the reduced coil vibrator is radiated from the surface of the coil vibrator toward the outside of the loop, but the inclination is such that the diameter is reduced. It is difficult to distribute the magnetic field of the magnet plate 20 so as to be parallel to the plane of vibration in the direction. Therefore, the coil vibrator having a reduced diameter is a coil vibrator having a diameter increased such as a region where the angle of the magnetic field direction with respect to the magnet plate 20 is large or a region where the magnetic field strength is high to a position away from the magnet plate 20. It is good to adopt in the area which is not suitable.
The coil vibrating body 30A on the inner circumferential side is used with a diameter reduction since the distribution of the magnetic field in the installed region meets these conditions, and as shown in FIG. 4, the inclination direction of the vibrating surface 33A and the magnetic field The reason for the deviation of the direction is that it is difficult to make the direction of the magnetic field of the magnet plate 20 coincide with the inclination direction of the vibration surface 33A of the coil vibrator 30A.
Here, although the coil vibrator 30A is used after being contracted, by making the vibration surface 33A 90 degrees, ie, perpendicular to the front surface of the magnet plate 20, the vibration surface 33A is brought close to the direction of the magnetic field to make the magnetic field Can increase the utilization efficiency of Further, as the angle of the magnetic field with respect to the front surface of the magnet plate 20 approaches 90 degrees, the vibration of the coil vibrator increases parallel components with respect to the surface of the magnet plate 20, and the directivity characteristic of the directivity characteristic largely deviates from the central axis. I can expect improvement.
However, since the coil vibrator having a reduced diameter has a shape that diffuses sound as the coil vibrator 30A, it can also function as a diffuser. Therefore, in the present embodiment, this function is used to set an angle to reflect and diffuse the sound generated by the coil vibrating body 30B.

When a plurality of coil vibrators are arranged as in the present embodiment, it is necessary to consider the phase of the sound generated by each coil vibrator.
When the phases of the sounds generated by the coil vibrators 30A, 30B, and 30C according to the present embodiment are matched, the acoustic signal current is supplied in the same phase between the coil vibrator 30B and the coil vibrator 30C which are expanded in diameter. An acoustic signal current is supplied to the coil vibrating body 30A having a reduced diameter so as to have an opposite phase to the coil vibrating bodies 30B and 30C having the increased diameter.
Bonding between the conductors 31 is preferably performed on the back surface side of the coil vibrator regardless of whether or not the coil vibrators 30A to 30C are diameter-reduced or diameter-expanded. This is because sound is directly emitted from the conductor 31 without passing through an adhesive or the like, which is advantageous in sound quality.

Like the electro-acoustic transducer 10 of the first embodiment, the electro-acoustic transducer 10A of the second embodiment configured as described above can be used as a speaker, a headphone, or the like, or as a microphone, etc. It is possible to realize high sound quality of an electroacoustic transducer adopting a voice coil diaphragm.
In the present embodiment, since the outer diameter of the basic area magnet 22 is reduced to reduce the size of the magnet plate 20, the reduction rate of the magnetic field strength tends to increase with the distance from the front surface of the magnet plate 20. is there. Therefore, the plurality of coil vibrators 30A to 30C are arranged concentrically with a narrow width, and arranged in a region with high magnetic field strength close to the magnet plate 20, thereby preventing the reduction in efficiency even with a small size. The vessel 10A can be configured.

According to the electroacoustic transducer of the second embodiment configured as described above, the following operation can be obtained in addition to the same operation as that of the first embodiment.
(1) In order to arrange a plurality of coil vibrators different in size and characteristics concentrically (coaxially), combining the coil vibrators whose diameter is expanded toward the front of the magnet plate and the coil vibrators whose diameter is reduced Can. Therefore, the shape and inclination of the vibrating surface can be finely adjusted for each coil vibrator in accordance with the distribution of the magnetic field, and the utilization efficiency of the magnetic field can be enhanced.
(2) Further, by combining the respective coil vibrators as different characteristics, the whole can be made a composite type electroacoustic transducer excellent in acoustic characteristics. For example, frequency characteristics, directivity characteristics, efficiency, and the like can be finely adjusted by properly using the size and shape of the diaphragm, the inclination of the vibration surface, and the like for each coil vibrator.
(3) Since the coil vibrator is divided into a plurality of parts, the loop of the coil vibrator is unlikely to be high in the forward direction of the magnet plate. Therefore, the conductor of the coil vibrator is distributed at a position close to the magnet plate, that is, at a position where the magnetic field strength is high, and the utilization efficiency of the magnet becomes high. In addition, even when the coil vibrator is expanded in the forward direction of the magnet plate, sound is easily emitted to the outside.

Third Embodiment
An electroacoustic transducer in Embodiment 3 will be described. The same components as those in Embodiment 1 or 2 are assigned the same reference numerals and explanation thereof will be omitted.
FIG. 6 is a schematic cross-sectional schematic end view of an essential part in the height direction intermediate part of the coil vibrator of the electroacoustic transducer according to the third embodiment.
In FIG. 6, an electroacoustic transducer 10B according to the third embodiment is different from that according to the first embodiment in that the conductor 31 is wound so that the coil vibrator 30D has an elliptical shape.
An acoustic signal current flows through the elliptically wound conductor 31 and an electromagnetic force is generated alternately in the inward direction and the outward direction, thereby changing the ellipticity of the ellipse alternately to generate sound.
As in the first or second embodiment, the shape of the coil vibrating body 30D may be enlarged or reduced in diameter toward the front of the magnet plate, and may effectively function as a cylindrical shape. When the diameter is reduced and used, the valley fold 33y in FIG. 6 becomes a mountain fold 33x.
Since the structure of the coil vibrator 30D is not complicated, the electroacoustic transducer 10B is easy to design and manufacture, and has excellent versatility.
In the case of installing the coil vibrator with the diameter expanded or reduced, the surface on the side of the magnet plate is a back surface because the sound is hardly emitted to the outside, and the opposite surface is used as the surface. In any case, as the inclination angle of the magnetic field with respect to the front surface of the magnet plate becomes larger, the vibration of the coil vibrator increases in parallel component to the surface of the magnet plate. When the parallel direction component increases, good directivity characteristics can be obtained, but the vibration of the vertical direction component decreases and the efficiency in the central axis direction decreases, so it is better to use these features depending on the usage conditions.
In addition, coil vibration body 30D made into elliptical shape becomes easy to expand-contract in the inward and outward directions of a loop by elastic deformation by forming in a loop shape, providing repeatedly a small unevenness | corrugation in a vibration surface. When the coil vibrator 30D is easily expanded and contracted in the inward and outward directions of the loop, the influence of the vibration of each position of the coil vibrator on each other is reduced, and uniform frequency characteristics are easily obtained.

Next, a first modification of the electroacoustic transducer in the third embodiment will be described.
FIG. 7 is a cross-sectional schematic end view of relevant parts of a height-direction intermediate portion of a coil vibrator showing a first modification of the electroacoustic transducer in the third embodiment.
In FIG. 7, electro-acoustic transducer 10C in the first modification of the third embodiment is different from that of the third embodiment in that a plurality of coil vibrators 30D having a smaller size than that of the third embodiment are radially arranged. It is a point that
The shape of the coil vibrating body 30D may be increased in diameter toward the front of the magnet plate or may be reduced in diameter, and also functions effectively as a cylindrical shape. When the diameter is reduced for use, the valley fold 33y in FIG. 7 is a mountain fold 33x.
The plurality of coil vibrators 30D need not have the same diameter, diameter, and cylindrical shape as a whole, but can be selected from various combinations of the respective shapes according to the required characteristics. Become.
The electroacoustic transducer 10C can increase the occupancy rate of the conductor 31 as compared with the electroacoustic transducer 10B of the third embodiment, and is effective as a means for enhancing the utilization efficiency of the magnet.

Next, a second modification of the electroacoustic transducer in the third embodiment will be described.
FIG. 8 is a cross-sectional schematic end view of relevant parts of a height-direction intermediate portion of a coil vibrator showing a second modification of the electroacoustic transducer in the third embodiment.
In FIG. 8, electro-acoustic transducer 10D in the second modification of Embodiment 3 is different from that in Embodiment 3 in that conductor 31 of coil vibrating body 30E and coil vibrating body 30F has an arc shape or a crescent shape. In that the two valley folds 33y are provided and deformed so that the coil vibrators 30E and 30F of two large and small types are arranged opposite to each other along the circumference. is there.
The shapes of the coil vibrating body 30E and the coil vibrating body 30F may be enlarged or reduced in diameter toward the front of the magnet plate, and function effectively as a cylindrical shape. When the diameter is reduced for use, the valley fold 33y in FIG. 8 is a mountain fold 33x. The coil vibrating body 30E and the coil vibrating body 30F need not have the same diameter, diameter, and cylindrical shape as a whole.
The electro-acoustic transducer 10D can increase the occupancy rate of the conductor 31 similarly to the electro-acoustic transducer 10C of the first modified example, and is effective as a means for enhancing the utilization efficiency of the magnet.

Next, a third modification of the electroacoustic transducer in Embodiment 3 will be described.
FIG. 9 is a cross-sectional schematic end view of relevant parts of a height direction intermediate portion of a coil vibrating body showing a third modification of the electroacoustic transducer in the third embodiment.
In FIG. 9, an electroacoustic transducer 10E according to a third modification of the third embodiment is different from that of the third embodiment in that the conductor 31 is wound so that the entire shape of the coil vibrator 30G is spiral. It is the point being turned.
The shape of the coil vibrating body 30G may be increased in diameter toward the front of the magnet plate or may be reduced in diameter, and also functions effectively as a cylindrical shape. When the diameter is reduced and used, the valley fold 33y in FIG. 9 becomes a mountain fold 33x.
In one coil vibrating body 30D such as the electroacoustic transducer 10B of the third embodiment, the occupancy rate of the conductor 31 decreases and the utilization efficiency of the magnet decreases. Therefore, the electroacoustic transducer 10C of the first modification example Alternatively, in the electro-acoustic transducer 10D according to the second modification, the coil vibrators 30D or 30E, 30F are disposed to increase the occupancy rate of the conductor 31. In the electro-acoustic transducer 10E of the third modified example, the electro-acoustic transducer 10C of the first modified example is constructed by straddling the conductor 31 so that the entire shape of even one coil vibrating body 30G becomes spiral. Similarly to the electro-acoustic transducer 10D of the second modified example, the occupancy rate of the conductor 31 can be increased, which is effective as a means for enhancing the utilization efficiency of the magnet.
The coil vibrator 30G having a spiral shape is easily formed in a loop while repeatedly providing small irregularities on the vibration surface, so that elastic deformation makes it easy to expand and contract inward and outward of the loop. When the coil vibrator 30G is easily expanded and contracted in the inward and outward directions of the loop, the influence of the vibration of each position of the coil vibrator on each other is reduced, and uniform frequency characteristics are easily obtained.

Next, a fourth modification of the electroacoustic transducer in the third embodiment will be described.
FIG. 10 is a cross-sectional schematic end view of relevant parts of a height direction intermediate part of a coil vibrating body, showing a fourth modification of the electroacoustic transducer in the third embodiment.
In FIG. 10, electro-acoustic transducer 10F in the fourth modification of Embodiment 3 is different from that in Embodiment 3 in that coil vibrating body 30H has an elliptical shape in the central portion and an arc or crescent shape on both sides thereof. Is a point where the conductor 31 is wound so as to form a continuous loop.
The shape of the coil vibrating body 30H may be increased in diameter toward the front of the magnet plate or may be reduced in diameter, and also functions effectively as a cylindrical shape. When the diameter is reduced and used, the valley fold 33y in FIG. 10 is a mountain fold 33x and the mountain fold 33x is a valley fold 33y.
Even with one coil vibrator 30H that is easy to install, the occupied volume of the conductor 31 can be increased by complexly deforming the shape with the plurality of mountain folds 33x and valley folds 33y, and the use of magnets Efficiency can be improved. Moreover, since the shape of each portion of the coil vibrator is changed as compared to the electroacoustic transducer 10E of the third modification, frequency characteristics, directivity characteristics, and efficiency can be obtained by properly using the inclination and shape of the vibration surface for each portion. Etc. can be finely adjusted.
The coil vibrator 30H having an elliptical shape or a bow shape can be easily expanded and contracted inward and outward of the loop by elastic deformation by repeatedly forming small irregularities on the vibration surface and forming it in a loop. When the coil vibrator 30H is easily expanded and contracted in the inward and outward directions of the loop, the influence of the vibration of each position of the coil vibrator on each other is reduced, and uniform frequency characteristics are easily obtained.

According to the electroacoustic transducer of the third embodiment configured as described above, the same operation as that of the first embodiment can be obtained.
As described above, the coil vibrator used in the present invention can operate in various shapes and sizes, and can be used in various combinations to constitute an electroacoustic transducer.
Basically, when the conductor is wound in a shape other than a circle, the coil vibrator easily generates a sound. Even if it is circular, by forming it in a loop while repeatedly providing small irregularities on the vibration surface, it is possible to easily generate sound by being able to expand and contract inward and outward directions of the loop by elastic deformation of the irregularities.

Hereinafter, the present invention will be specifically described by way of examples. The present invention is not limited to these examples.
Example 1
An electroacoustic transducer 10 having the same configuration as that of the first embodiment was produced.
<Configuration of magnet plate>
The central area magnet 21 is axially magnetized by a cylindrical neodymium magnet having an outer diameter of 18 mm, an inner diameter of 5 mm, and a height of 8 mm. Further, the basic area magnet 22 is a cylindrical shape having an outer diameter of 36 mm, an inner diameter of 18 mm, and a height of 8 mm as a whole, and the upper base 2.8 mm, the lower base 5.6 mm, and the height 8. Sixteen 7 mm trapezoidal neodymium magnets (small magnets 22b) are combined. The magnet plate 20 is configured by combining the two types of central area magnets 21 and basic area magnets 22.
<Creation of coil vibrator>
First, three conductors 31 made of insulated copper clad aluminum wire with an outer diameter of 80 μm of the conductor portion are aligned in parallel and wound in a single layer to form a thin ring having an inner diameter of 20 mm and an outer diameter of 34 mm. Furthermore, an adhesive was applied to the back surface side and fixed to form a planar coil. Thereafter, the coil vibrating body 30 was formed by pressing the mold formed in the same shape as the coil vibrating body 30 shown in FIG. 3. The diameter of the smallest portion of the coil vibrator 30 was 10 mm, the diameter of the largest portion was 24 mm, and the height of the lowest portion of the outer peripheral edge was 5 mm, and the height of the highest portion was 8 mm.
<Characteristics>
The impedance of the electroacoustic transducer 10 using the magnet plate 20 and the coil vibrating body 30 which were comprised as mentioned above became 4 (ohm). In addition, the output sound pressure level (2.83 V / 1 m) averages 85 dB between 2.5 kHz and 20 kHz, and the second and third harmonic distortions in this band are both less than 0.3%. The
Moreover, the change of the output sound pressure level in the direction of 30 degrees with respect to the central axis direction has a result of -2 dB at around 10 kHz and -4 dB at around 20 kHz as an average value.
In the speaker with an outer diameter of 24 mm of the voice coil diaphragm manufactured according to (Patent Document 4), the change of the output sound pressure level in the direction of 30 degrees as an average value is -5 dB at around 10 kHz and -9 dB at around 20 kHz It was a degree. Therefore, in the present embodiment, the change of the output sound pressure level in the direction of 30 degrees with respect to the central axis is improved by +3 dB at around 10 kHz and by +5 dB at around 20 kHz. Although the present embodiment is created as a simple general example of the present invention and is not intended to improve the directivity characteristics, the directivity characteristics are thus greatly improved.
As described above, the electro-acoustic transducer 10 of the present embodiment achieves sufficient results in directivity characteristics, harmonic distortion, output sound pressure level, and the like by utilizing the perpendicular magnetic field component of the magnetic field formed by the magnet plate 20. Can be used to further enhance the performance of speakers that use high-quality voice coil diaphragms

(Example 2)
When the basic area magnet 22 in Example 1 was abolished and only the central area magnet 21 having an outer diameter of 20 mm was used as the magnet plate 20, in the coil vibrating body 30 part, the distribution of the magnetic field similar to Example 1 was obtained. .
Although the magnetic field strength at each position of the coil vibrator 30 is reduced to about half that of the first embodiment, the output sound pressure level is also reduced, but the amount of use of the magnet can be reduced to about one third.
Thus, the coil vibrator of the present invention can not only be operated with respect to various magnetic field distributions, but can also be operated with a very simple magnet plate of only one type of cylindrical magnet.
Further, since the magnet plate 20 can be made small to miniaturize the electroacoustic transducer 10, it can also be adopted for high-quality headphones. Furthermore, due to its simple structure, it can be suitably used in earphones, microphones, etc. where precise work is required by promoting miniaturization, and high sound quality of an electroacoustic transducer employing a voice coil diaphragm is easily realized. become able to.

  The present invention realizes a new vibration form by utilizing not only the parallel magnetic field component of the magnetic field formed by the magnet plate but also the perpendicular magnetic field component in the electroacoustic transducer adopting the voice coil diaphragm, thereby achieving a further high vibration. It aims at performance and diversification. A speaker with excellent magnet utilization efficiency and extremely good directional characteristics is realized by utilizing the perpendicular magnetic field component, and this high-range speaker is dedicated to a coaxial speaker that is considered as an ideal multi-way speaker. It is possible to install it without providing a magnetic circuit, thereby realizing the miniaturization of the whole size and adapting it to various usage forms. In this way, an electroacoustic transducer excellent in sound quality, versatility, mass productivity and resource saving is provided, and conversion from electric signals to sounds of speakers, headphones, earphones, etc., or microphones, acoustic wave sensors Etc. It can contribute to the efficiency improvement in conversion from sound to electric signal.

10, 10A, 10B, 10C, 10D, 10F Electroacoustic Transducer 20 Magnet Plate 21 Central Area Magnet 21a, 53a, 54a Bolt Insertion Hole 22 Basic Area Magnet 22a, 54b Sound Passing Hole 22b Small Magnet 30, 30A, 30B , 30C, 30D, 30E, 30F, 30G, 30H Coil vibrator 31 Conductor 33, 33A, 33B, 33C Vibration plane 33x Mountain fold 33y Valley fold 40, 40A Tubular frame 40a Front support frame 40b Opening 41, 41A Inner peripheral side support portion 42, 42A Outer peripheral side support portion 43A, 44A Intermediate support portion 45 Sound absorbing material 51 Outer peripheral frame 52 Intermediate frame 53 Central frame 54 Rear frame 56 Bolt 57 Nut

Claims (3)

(A) a magnetic field formed by the magnet plate, and a coil vibrator, the magnet plate having a magnet plate and a coil vibrator formed by winding a conductor and disposed in front of the magnet plate; The coil vibrator is vibrated to generate a sound by an electromagnetic force generated by an acoustic signal current flowing in a conductor, or (b) the magnetic field formed by the magnet plate and the vibration of the coil vibrator due to the sound An electro-acoustic transducer that generates an acoustic signal current in the conductor of the coil diaphragm,
The coil vibrator has a vibrating surface inclined with respect to the front surface of the magnet plate or a vibrating surface perpendicular to the front surface of the magnet plate, the vibrating surface is formed in a loop shape, and the coil vibrator is An electro-acoustic transducer characterized in that its vibration has a component parallel to at least the front surface of the magnet plate.   The electro-acoustic transducer according to claim 1, wherein the vibration surface of the coil vibrator is formed in a loop shape while repeating unevenness.   The electroacoustic transducer according to claim 1, wherein a plurality of the coil vibrators are provided.