JPH06113394A - Electroacoustic transducer - Google Patents

Abstract

PURPOSE:To provide the electroacoustic transducer in which a base part is simplified by adopting a hybrid method for base members. CONSTITUTION:The electroacoustic transducer is the one in which a diaphragm 30 and a magnetic drive section 5 receiving an electric signal and vibrating the diaphragm magnetically are built in an outer case 2, a base member metal base 40 used to clog a back surface side opening of the outer case is formed of a metallic plate, coil leads of the magnetic drive section are led out through a throughhole or a notch formed on the base member and the lead section of the coil of the magnetic drive section are connected to terminal conductor patterns 50, 52 formed on the front surface of the base member with an insulation film 48 interposed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electroacoustic transducer for converting an input electric signal into sound.

[0002]

2. Description of the Related Art Conventionally, an electromagnetic electroacoustic transducer is shown in FIG.
Further, as shown in FIG. 7, a cylindrical outer case 2 formed of synthetic resin is provided, and a base portion 4 is installed on the opening side of the outer case 2. The base portion 4 is a closing means that closes the opening of the outer case 2 and a portion that functions as a support member for the magnetic drive portion 5. The iron core 6, the base 8, the substrate 10, and the terminal 1 are provided.
2, 14 and caulking pins 16 and 18 are composed of 7 parts of 5 types. That is, the substrate 10 and the base 8 are fixed by caulking the rear portion of the iron core 6. The base portion 4 has a double structure including the substrate 10 and the base 8, and the substrate 10 is provided with the crimping pins 16 and 18 on the terminal 1.
2 and 14 are fixed.

The iron core 6 constitutes a part of the magnetic drive unit 5, around which a coil 20 is wound, and its lead portions 22 and 24 are individually connected to the terminals 12 and 14. An annular magnet 26 fixed to the base 8 is installed around the coil 20.

Further, in this electroacoustic transducer, a step portion 27 is provided inside the outer case 2 so that the front side has a small diameter and the rear side has a large diameter, and is supported between the step portion 27 and the base 8. A space retaining ring 28 as a member is installed. A vibration plate 30 for converting magnetic vibrations into mechanical vibrations is installed on a seating surface formed on the inner peripheral portion of the space retaining ring 28. The vibrating plate 30 is installed with a gap 32 between the vibrating plate 30 and the end surface of the iron core 6 to allow mechanical vibration. A magnetic piece 34 is fixed to the diaphragm 30, and a resonance space 36 for causing resonance vibration is provided inside the exterior case 2 on the front side thereof. A cylindrical sound emission hole 38 that opens the resonance space 36 to the outside air is formed on the front surface side of the outer case 2.

Therefore, in such an electroacoustic transducer, when an electric signal of an appropriate level is applied to the terminals 12 and 14, the coil 20 is excited by the electric signal,
The vibration causes the diaphragm 30 to vibrate vertically in the drawing. The vibration of the diaphragm 30 depends on the amplitude and frequency of the applied electric signal. As a result, the sound generated by the vibration of the diaphragm 30 is emitted to the outside air from the sound emitting hole 38 while being accompanied by the resonance vibration of the resonance space 36. In this case, the base portion 4 also has a function of keeping airtightness from the back surface side of the diaphragm 30, and contributes to a certain acoustic characteristic in generating sound.

[0006]

By the way, in such an electroacoustic transducer, the base portion 4 in the outer case 2 is used.
Is a very large proportion, which hinders its size and weight reduction. Conventionally, for downsizing and weight reduction,
Although the iron core 6 has been shortened, such a method affects the number of windings of the coil 20 and the winding form, and the flattening of the electroacoustic transducer lowers the generated magnetic field, that is, the magnetic drive. There is a drawback that the force is lowered and the sound pressure is lowered.

Further, reducing the resonance space 36 that occupies a large volume in the outer case 2 is effective for downsizing the electroacoustic transducer. The resonance space 36 plays an important resonance effect in generating sound. Therefore, the narrowing thereof deteriorates the resonance effect and has a bad influence on the acoustic characteristics far more than the reduction of the magnetic driving force, which is not a good idea.

Therefore, the present inventor has proposed an electroacoustic transducer having a flat base portion without sacrificing the characteristics of the electroacoustic transducer.

Therefore, an object of the present invention is to provide an electroacoustic transducer in which the base portion is simplified by hybridizing the base member.

[0010]

As shown in FIG. 1, the electroacoustic transducer of the present invention includes a diaphragm (30) in an outer case (2) and a magnetic diaphragm that receives an electric signal and is magnetically received. In the electroacoustic transducer having a built-in magnetic drive unit (5) for vibrating, the base member (metal base substrate 40) for closing the rear side opening of the outer case is formed of a metal plate, and the magnetic drive unit is provided. The lead portion of the coil is drawn out through through holes (54, 56) or notches formed in the base member, and a terminal pattern (conductive pattern) formed by interposing an insulating film (48) on the surface of the base member. 50, 52) is connected to the lead portions (22, 24) of the coil of the magnetic drive unit.

[0011]

In the electroacoustic transducer of the present invention, the base member is formed of a metal plate, and the terminal pattern is formed on the base member with an insulating film interposed. Then, the base member is formed with a through hole or a notch for drawing out the lead part of the coil of the magnetic drive part, and the lead part drawn out through the through hole or the notch has a terminal pattern. As a result, the thickness of the base portion or the occupied volume is reduced.

Further, such simplification of the base member contributes to the effect of suppressing unnecessary vibration and also contributes to the improvement of acoustic characteristics.

[0013]

The present invention will be described in detail below with reference to the embodiments shown in the drawings.

1 and 2 show one embodiment of the electroacoustic transducer of the present invention. In this electroacoustic transducer, a single metal base substrate 40 is used as a plate-shaped base member formed of a metal material in the base portion 4. The metal base substrate 40 is formed by forming a terminal portion 44, which is formed by extending a part thereof in a diametrical direction, in a circular closing portion 42 that closes the opening on the back side of the outer case 2. In the case of this embodiment, a bent portion 46 bent into an L-shape is formed on the outer case 2 side.

An insulating film 48 is formed on the outer surface of the closing portion 42 and the terminal portion 44 of the metal base substrate 40 by printing or applying an insulating paste or the like. Further, a conductive paste is selectively printed on the surface of the insulating film 48 by using the insulating film 48 as an insulating means.
Conductive patterns 50 and 52 are formed as a plurality of terminal patterns by a conductor forming means such as plating. The conductive patterns 50 and 52 may be used for mounting a circuit or an element associated with the electroacoustic transducer for downsizing and simplification of an electronic device, and need not be a mere lead.

In the case of this embodiment, the lead portions 22, 24 of the coil 20 of the magnetic drive unit 5 incorporated in the outer case 2 are provided in the closed portion 42 at a position slightly separated from the central portion thereof.
Through holes 54 and 56 are formed for drawing out. The through holes 54 and 56 are formed by punching a metal plate as a material before the metal base substrate 40 is bonded to the outer case 2. Since the through holes 54 and 56 are means for pulling out the lead portions 22 and 24 of the coil of the magnetic drive unit 5 to the back side of the metal base substrate 40, the through holes 54 and 56,
It is also possible to form a single or a plurality of notches having the same function as 56 in the edge portion of the metal base substrate 40 and the like, and to lead out the lead portions 22 and 24 with the notches.

The lead portions 22 and 24 drawn out from the through holes 54 and 56 are electrically connected to the conductive patterns 50 and 52 with solder or a conductive adhesive. Also,
The through holes 54 and 56 are filled with an insulating agent 53 as an insulating means and a fixing means. As a result, the lead portion 2
It is possible to prevent unnecessary stress from being applied to the wires 2 and 24, protect the electroacoustic transducer from an accident such as disconnection, and contribute to improvement in reliability of the electroacoustic transducer.

The outer case 2 has a cylindrical shape formed by molding a synthetic resin, and its basic structure is the same as that of a conventional electroacoustic transducer, but in this embodiment, a metal base substrate 40 is used as a base. Since the portion 4 is configured, it is flattened. Further, since the effective length of the iron core 6 in the base portion 4 is set to a length excluding the portion of the iron core 6 penetrating the substrate 10 and the crimped portion in FIG. 6, in the electroacoustic transducer of this embodiment. The effective length of the iron core 6 is obviously short, which also shows that the height of the electroacoustic transducer is low.

A through hole 58 is formed in the central portion of the metal base substrate 40, and the small diameter portion 60 of the iron core 6 is press-fitted and fixed in the through hole 58 to stand upright. That is, the iron core 6 does not have the additional function of the conventional coupling means but simply functions as the magnetic core.
In this way, the iron core 6 and the metal base substrate 40 magnetically form a closed circuit and form a part of the magnetic path of the magnetic drive unit 5. Further, as a fixing means of the iron core 6, a small diameter portion 60
Also, various methods such as welding and fixing with an adhesive can be used in addition to the method of screwing the through hole 58 and screwing.

A coil 20 is wound around the iron core 6 and an annular magnet 2 is formed around the coil 20.
6 is installed to configure the magnetic drive unit 5. The magnet 26 is firmly fixed to the upper surface of the metal base substrate 40 with an adhesive or the like, with a slight distance from the periphery of the coil 20.

A diaphragm 30 is installed which forms a closed magnetic path with the magnet 26 and is driven by the oscillating magnetic field from the iron core 6 in the magnetic drive unit 5. The peripheral edge of the vibration plate 30 is fixed to a seating surface formed on the inner peripheral portion of the spacing ring 28 provided so as to surround the magnet 26. Inside the outer case 2, a step portion 27 is provided to form a small diameter on the front side and a large diameter on the rear side, and the large diameter portion is fitted with a spacing ring 28 for mechanical positioning and fixing. It has been done.

Further, in the center portion on the outer surface side of the diaphragm 30,
A magnetic piece 34 for fixing the mass to the diaphragm 30 and improving the magnetic efficiency is fixed. A resonance space 36 is formed by the exterior case 2 on the front side of the vibration plate 30, and a cylindrical sound emission hole 38 that opens the resonance space 36 to the outside air is provided in a form facing the magnetic piece 34. Has been.

Next, FIG. 3 shows a concrete example of the metal base substrate 40. The metal base substrate 40 is
It is a closing means for closing the outer case 2, and magnetically constitutes a part of the closed magnetic path and is made of a metal plate so as to have appropriate rigidity. Therefore, the conductive pattern 5 forming a terminal for pulling out the lead portions 22 and 24 to the outside
0 and 52 are formed. In this embodiment, the insulating coating 48 is formed on the surface of the metal base substrate 40 with an insulating paste or the like, and the conductive pattern 5 is formed on the surface with the conductive paste.
0 and 52 are formed. The insulating film 48 may be formed of an insulating paint, an oxide film or the like, and the conductive patterns 50 and 52 may be formed of copper foil or the like.

According to this structure, as shown in FIG. 4, the closing portion 42 and the terminal portion 44 are placed in accordance with the conductive pattern 64 of the printed circuit board 62 of the electronic device, and electrically connected with the solder 66. , Can be mechanically fixed. That is, there is no need to provide a separate member for installing the electroacoustic transducer, and the mechanical structure and electrical connection structure around the electroacoustic converter can be simplified.

In this electroacoustic transducer, the iron core 6
Of the magnetic drive unit 5 such as the effective length of the magnet 26 and the magnet 26, the base unit 4 is simplified by using the metal base substrate 40. Since it is not used as a connecting member for members other than the function, and the conventional length for crimping is not required, the structure is simplified by reducing the number of parts, and the processing or assembly process is simplified. I was able to achieve this. In addition, the use of the metal base substrate 40 has an effect of suppressing unnecessary vibration, which contributes to improvement of acoustic characteristics.

Next, FIG. 5 shows another embodiment of the electroacoustic transducer of the present invention. That is, the metal base substrate 40
The bent portion 46 provided on the terminal portion 44 may be formed toward the back side as shown in FIG. 5, and its form does not hinder the hybridization. In particular, the electroacoustic transducer using the metal base substrate 40 brings about not only the flattening but also a change in the terminal form. It will increase the degree. Therefore, according to such a configuration, the through hole 68 into which the bent portion 46 can be inserted is formed on the printed circuit board 62 side to which the electroacoustic transducer is attached,
After the bent portion 46 is inserted and temporarily fixed therein, solder 66 or a conductive adhesive is placed between the bent portion 46 and the conductive pattern 64 on the back surface side, so that it can be mechanically fixed together with electrical connection. . Compared with the embodiment shown in FIG. 4, there is an advantage that the fixing strength to the printed board 62 is further increased and the reliability can be improved.

In the embodiment, the case where the terminal portion 44 and the printed circuit board 62 are connected or fixed with solder or a conductive adhesive has been described. However, the electroacoustic transducer of the present invention includes screws and nuts. A mechanical fixing means, a means such as cutting and raising of the chassis may be used, and the flexibility of the fixing means is not impaired.

Further, in the embodiment, it is emphasized that the electroacoustic transducer is flattened and downsized by using the metal base substrate 40 which is a base member. In the configuration, even if the conventional electroacoustic transducer has the same internal form and the metal base substrate 40 is installed on the outer surface side thereof to sacrifice the flatness, the advantage of changing the form of the terminal structure should be ignored. I can't.
Therefore, the electroacoustic transducer of the present invention is not limited to the form of the magnetic drive unit of the electroacoustic transducer of the embodiment.

In the embodiment, the through holes 54 and 56 are formed in the metal base substrate as the lead-out means for the lead portions 22 and 24. However, as an application example thereof, a through hole is formed in the metal base substrate 40. Alternatively, the conductive pattern may be formed by interposing an insulating coating on the formed portion, and the lead portions 22 and 24 of the coil 20 may be connected to the conductive pattern on the upper surface side of the metal base substrate 40.

[0030]

As described above, according to the present invention,
The conventional terminal is metalized on the base member, and a terminal pattern is formed by interposing an insulating film on the surface to form a terminal, and the lead portion of the coil of the magnetic drive unit is connected to this terminal pattern, which simplifies the configuration. In addition, the electroacoustic transducer can be flattened, and the acoustic characteristics can be improved.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of the electroacoustic transducer of the present invention.

FIG. 2 is a plan view showing a back surface portion of the electroacoustic transducer shown in FIG.

3 is a cross-sectional view showing a configuration of a metal base substrate in the electroacoustic transducer shown in FIG.

FIG. 4 is a vertical cross-sectional view showing a mounted state of the electroacoustic transducer shown in FIG.

FIG. 5 is a vertical cross-sectional view showing another embodiment of the electroacoustic transducer of the present invention and a mounting state thereof.

FIG. 6 is a vertical sectional view showing a conventional electroacoustic transducer.

FIG. 7 is a plan view showing a back surface portion of the electroacoustic transducer shown in FIG.

[Explanation of symbols]

 2 Outer case 5 Magnetic drive part 20 Coil 22,24 Lead part 30 Vibrating plate 40 Metal base substrate (base member) 48 Insulating film 50,52 Conductive pattern (terminal pattern) 54,56 Through hole

Claims (1)

[Claims] 1. An electroacoustic transducer comprising an outer case, a diaphragm, and a magnetic drive unit for magnetically vibrating the diaphragm in response to an electric signal. The base member to be closed is formed of a metal plate, and the lead portion of the coil of the magnetic drive unit is pulled out through a through hole or a notch formed in the base member, and an insulating film is formed on the surface of the base member. An electroacoustic transducer, wherein the lead portion of the coil of the magnetic drive unit is connected to the terminal pattern.