JP2000078688A - Electric / acoustic converter - Google Patents

Abstract

(57) [Problem] To provide an electro-acoustic conversion device that is thin and can strongly reproduce a high frequency band when obtaining a coaxial speaker unit or a coaxial headphone unit. SOLUTION: A diaphragm (diaphragm) 17 is arranged behind a frame 14 or a flange portion 12a, and an inner and outer magnetic type magnetic circuit is coaxially arranged in front of the frame or the flange portion 12a to form an outer magnetic type magnetic circuit. A diaphragm 9 for high sound is provided in the frame 14 or the flange 1 by an internal magnet type magnetic circuit.
By driving the diaphragm (diaphragm) 17 behind 2a, the magnetomotive force of the magnet of the internal / external magnetic type magnetic circuit can be added.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric / acoustic converter suitable for use in a small-sized speaker device or headphone device, and more particularly to a high-sensitivity coaxial small-sized electric device having a wide reproduction band from a high frequency range to a low frequency range. -It relates to an acoustic conversion device.

[0002]

2. Description of the Related Art Conventionally, coaxial speaker units have been widely used because high-, low-, and mid-range sound sources can be emitted from the same location. A low-pitched speaker unit is assembled, and a separately assembled high-pitched tweeter is coaxially arranged approximately at the center of the diaphragm of the low-pitched speaker unit. Since the magnetic circuit and the magnetic circuit of the loudspeaker unit are provided independently, the coaxial type speaker unit has a large depth, and even when it is put into a speaker box or the like, it is difficult to reduce the size.

In particular, a case where a coaxial type speaker device in which a speaker unit having a diameter of about 65 mmφ and a book shell type speaker box is used to emit middle to low to high sounds with high sensitivity without deteriorating sound quality is obtained. However, since the magnet used in the magnetic circuit is small and a strong magnet cannot be used, it is difficult to reproduce with good sound quality over a wide reproduction band.

An object of the present invention is to provide an electro-acoustic converter such as a speaker device or a headphone device which solves the above-mentioned problems. It is an object of the present invention to obtain an electro-acoustic conversion device having good sound quality and high sensitivity from middle to low to high tones.

[0005]

According to the present invention, there is provided an electro-acoustic converter in which a dome-shaped diaphragm for high sound is pivotally mounted on an external magnetic circuit so as to swing forward. Means, and a second electro-acoustic conversion means in which a middle / low sound diaphragm is pivotably connected to the back of the inner magnet type magnetic circuit disposed on the rear surface of the outer magnet type magnetic circuit. The first electric / acoustic converter is coaxially arranged on the second electric / acoustic converter.

According to the present invention, a dome-shaped high-frequency sound diaphragm is arranged in the magnetic gap of the outer magnetic circuit, and an inner magnetic circuit is formed on the rear surface of the outer magnetic circuit. This inner-magnet type magnetic circuit is fixed to the frame, and the diaphragm for middle and low frequencies is arranged behind the frame.Therefore, a coaxial type conversion means in which the diaphragm for middle and low frequencies and the diaphragm for high sounds are arranged in a small depth is used. With this configuration, the center of the sound source from low to high pitches can be easily adjusted, and a device suitable for a small-sized electro-acoustic converter can be obtained.

Further, according to the present invention, the magnetic flux of the magnet of the inner magnetic circuit is added to the magnet of the outer magnetic circuit, so that the first electro-acoustic converter can be driven with a stronger magnetic flux. -A sound conversion device is obtained.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a speaker, a speaker device, a headphone unit and a headphone device as an electric / acoustic conversion device of the present invention will be described with reference to FIGS.
Further, the magnetic circuit will be described in detail with reference to FIG.

In FIG. 1, reference numeral 1 denotes a coaxial type speaker unit as a whole, in which a high-frequency speaker (hereinafter referred to as a tweeter) 2 and a medium / low-frequency speaker (hereinafter referred to as a squawker) 3 are coaxially arranged. It is arranged.

First, the description will be made from the configuration of the tweeter 2.
The magnetic circuit of the tweeter 2 is of an outer magnet type, and the yoke 4 is formed in a substantially disk shape. The cross section of the disk is substantially inverted T-shape by a conductive metal having a cylindrical center pole 4a erected at the center of the disk. It is integrally molded to form a shape.

The magnet 6 is formed in a ring shape and is joined and fixed on the disk of the yoke 4 via an adhesive. The magnet 6 may be magnetized in advance in the thickness direction with, for example, SN, but may be magnetized after the tweeter 2 is assembled.

An adhesive is applied to the upper surface of the ring-shaped magnet 6 to form a plate 7 made of a ring-shaped conductive metal.
To join. At this time, the jig is inserted into the center pole 4a, and the plate 7 is fixed so that the first magnetic gap 8 formed between the inner diameter of the plate 7 and the outer diameter of the center pole 4a is constant.

The dome-shaped diaphragm 9 and the voice coil bobbin 9a are integrally formed, and the voice coil bobbin 9a
Is wound with a voice coil 10.

The diaphragm 9 is integrated with the edge 9b, and is formed using, for example, a polyester film or the like.

The voice coil 10 wound around the voice coil bobbin 9a is inserted into the magnetic gap 8, and the outer periphery of the edge portion 9b is fixed on the plate 7 with an adhesive or the like. It is pivotally mounted so that it can swing up and down.

A columnar magnet 11 serving as an inner magnetic type magnetic circuit for the squawker 3 is bonded and fixed to the lower side of the yoke 4 of the tweeter 2 assembled as described above via an adhesive.

The magnet 11 has a thickness S.
It may be magnetized with N or may be magnetized simultaneously with the outer magnet 6 after assembling the magnetic circuit.

Next, a cylindrical second yoke 12 having a flange 12a at the lower end is joined to the outer peripheral portion of the lower surface of the yoke 4 with an adhesive or the like. Alternatively, the cylindrical second yoke 12 having the flange portion 12a may be formed simultaneously with the yoke 4 having the center pole 4a.

By forming a second magnetic gap 13 having a predetermined gap between the outer peripheral portion of the columnar magnet 11 and the inner diameter of the cylindrical second yoke 12, the inner magnetic type magnetic circuit portion of the squawker 3 is formed. Is completed.

Next, a through hole is provided in the bottom of the metal frame 14 formed in a substantially funnel shape, and a second hole is formed in the bottom inner surface.
Is placed and fixed with rivets or the like.

Next, a gap guide is inserted into the cylindrical magnet 11, and the voice coil bobbin 15 around which the voice coil 5 is wound is inserted outside the cap guide.

Next, the inner diameter of a ring-shaped normal damper 16 having a corrugated corrugation is joined to a substantially middle position of the voice coil bobbin 15, and the outer diameter of the damper 16 is adjusted to the vicinity of the outer periphery on the back side of the bottom of the frame 14. To hold the voice coil 5 swingably in the up-down direction.

Next, the inner diameter of the diaphragm 17 having a parabolic cone shape is joined to the lower end of the voice coil bobbin 15.

The diaphragm 17 may be a fixed edge integrated with the edge 18 or a configuration in which a ring-shaped edge having a small convex portion is joined to the outer peripheral portion of the parabolic cone-shaped diaphragm 17.

The outermost peripheral portion of the edge 18 is joined to the outermost diameter portion of the frame 14 via arrow paper 19.

When the joining and drying of the damper 16 and the diaphragm 17 are completed, the gap guide is removed, and the cap 20 is covered with the lower end of the voice coil bobbin 15 and joined.

The cap 20 has a concave shape so as to reduce the depth of the entire speaker unit 1. Further, the frame 14 is provided with a plurality of relatively large openings 14a in order to transmit the vibration emission from the diaphragm 17 at the rear of the frame 14 to the front (upward in FIG. 1).

A speaker device in which the above-described speaker unit 1 is built in a speaker box 22 will be described with reference to a side sectional view of FIG.

The speaker box 22 is made of a synthetic resin such as ABS and is formed into a box shape integrally with the baffle plate 22a and the phase inversion type duct 23, and the back plate is formed of a substantially square plate.

The speaker unit 1 is fixed in a normal manner so as to face the speaker sound emission hole 24 formed above the baffle plate 22a, and a phase inversion type speaker device 25 using a core axial type speaker is constructed.

In the speaker unit 1 of this embodiment, one end of a lead wire taken out from the voice coil 5 for the squawker 3 and a lead wire taken out from the voice coil 10 of the tweeter 2 are connected in series, and are fixed to the frame 14. Terminal 14
b, the insulation terminal 14b and the squawker diaphragm 17
It is connected to an input terminal 27 fixed to the back plate via a tinsel wire 26 and a lead wire 28 connected therebetween, and an acoustic signal is input from the input terminal 27 to the squawker 3 and the tweeter 2 in series. Needless to say, an acoustic terminal may be supplied in parallel by separately providing an insulated terminal for the tweeter.

According to the configuration of the speaker device as described above, the depth direction of the speaker unit 1 is extremely thin without projecting backward by the amount of the magnetic circuit, so that the depth of the speaker box 22 can be reduced and the speaker suitable for the book shell type. The device can be provided. The magnetic circuit for the tweeter and the magnetic circuit for the squawker can add the magnetic flux of the magnetomotive force of one magnet to the magnetic flux of the magnetomotive force of the other magnet by appropriately selecting the magnetization direction as described later. Therefore, even a speaker unit having a small diameter can increase the magnetomotive force.

FIG. 3 shows another embodiment of the present invention, and is a side sectional view in the case where the electric / acoustic converter is used for the headphone unit 28 or the headphone device 29.

First, the configuration of the headphone unit 28 will be described with reference to a side sectional view shown by a solid line in FIG.

In the headphone unit 28 of FIG.
Since the magnetic circuit used in this example has substantially the same configuration as the outer magnetic circuit and the inner magnetic circuit used for the speaker unit 1 of FIG. 1, the corresponding parts are denoted by the same reference numerals, and redundant description will be omitted. Hereinafter, only different parts will be described.

The high-frequency diaphragm 9 and the edge portion 9b and the diaphragm extension 31 of this embodiment are integrally formed of a conductive metal plate or the like.

A drive coil 30 in which a coil formed by winding an iron wire or the like in a ring shape is insulated on the ring-shaped magnet 6 constituting the external magnet type magnetic circuit, and the inner diameter of the ring-shaped drive coil 30 and the center are centered. A magnetic gap 8 is formed between the outer diameter of the pole 4a and the diaphragm extension 31 inserted into the magnetic gap 8 to supply an acoustic signal to the drive coil 30 to provide a light-weight diaphragm by the electromagnetic induction method. 9 is swung in the directions of arrows A and B to emit a sound signal.

The magnetic circuit for driving the diaphragm 17 for the low and middle sounds is of an inner magnetic type, and is formed below the yoke 4 of the outer magnetic type magnetic circuit.

The pole piece 3 is located below the magnet 11.
2 and the flange portion 12a of the second yoke 12 is provided with a large outer diameter and a circumferential portion 12b extending downward from the outer periphery of the flange portion 12a.

A plurality of openings 33 are formed in the flange portion 12a of the yoke 12 in the circumferential direction, and the voice coil is swingably inserted into the magnetic gap 13 formed between the second yoke 12 and the pole piece 32. A dome-shaped middle / low-frequency sound diaphragm 17 having an edge 5 is joined in the circumferential portion 12b.

In the diaphragm 17 for the middle and low frequency range, the portion that becomes the conventional dome-shaped diaphragm functions as a cap in this example, and the dome-shaped edge portion functions as a diaphragm (diaphragm).

Accordingly, by supplying a predetermined sound signal to the voice coil 5, sound is emitted from the middle / low sound diaphragm 17 in the directions of arrows C and D through the opening 33 formed in the flange portion 12a.

The outer circumference of the diaphragm 17 for middle and low frequency is held by the circumferential portion 12b via a diaphragm ring 34, and the protector 35 in the form of a cap is held on the inner circumference of the circumferential portion 12b. A plurality of openings 3 are provided on the bottom of the protector 35.
6 is pierced, and a resistor 37 such as resistance paper is attached so as to close the opening 36. Further, a dome-shaped protector 39 having a plurality of openings 38 is fixed to the outer peripheral portion of the yoke 4 so as to cover the magnetic circuit on the tweeter 2 side and the diaphragm 9. Reference numeral 40 denotes an input terminal board for driving the diaphragm 17 for the tweeter 2 and the middle / low sound.

The above configuration shows the configuration of the headphone unit 28. The headphone unit 28 is connected to the left and right headphone units 28 provided with the earpieces 42 and the casing 41 as shown by phantom lines by a headband. Thus, the headphone device 29 is formed.

A magnetic path used for the above-described speaker unit and speaker device, and a magnetic path used in the electric / acoustic conversion device constituted by the headphone unit and the headphone device is added to one magnetic path by referring to the magnetic path of the magnetic circuit. This will be described in detail with reference to FIGS. 4A and 4B.

FIGS. 4A and 4B are side sectional views when the magnets 6 and 11 of the magnetic circuit portion are magnetized with S and N in the thickness direction and have AA 'cross section in FIG. 4A. It is an arrow view.

In FIG. 4A, the description will be made using the magnetic circuit of the speaker unit 1 described with reference to FIG. The magnetic flux linked to the voice coil 10 for the tweeter 2 inserted into the magnetic gap 8 between the outer magnet type magnet 6 and the center pole 4a is the N pole of the magnet 6 → the yoke 4 → the center pole 4a → the inside of the magnetic gap 8 The voice coil 10 is driven by a closed circuit of the voice coil 10 → the plate 7 → the south pole of the magnet 6,
Similarly, the magnetic gap 1 held by the squawker diaphragm 17
The magnetic flux linked to the voice coil 5 inserted into the magnet 3 is used for the squawker by the closed circuit of the N pole of the magnet 6 → the voice coil 5 in the magnetic gap 13 → the second yoke 12 → the yoke 4 → the S pole of the magnet 11. Is driven.

Further, the magnet 1 for the inner magnet type squawker
The magnetic flux from the N pole of the first magnet is applied to the voice coil 5 in the magnetic air gap 13 → the second yoke 12 → the second yoke 12 as shown in FIG. From the lower side to the upper side, the yoke 4 passes through the outer periphery along the N pole of the magnet 6 as shown by an arrow E, and for example, the N side on the opposite side.
4B, the closed circuit of the magnetic flux of the S pole of the magnet 6 → the plate 7 → the voice coil 10 in the magnetic gap 8 → the center pole 4a → the S pole of the magnet 11 is formed from the lower side to the upper side in FIG. You.

Accordingly, in this case, the magnetomotive force of the magnet 11 of the inner magnetic type magnetic circuit for the squawker is added to the magnetomotive force of the magnet 6 of the outer magnetic type magnetic circuit on the tweeter 2 side, and the high-quality sound quality is improved.

[0050]

According to the present invention, the diaphragm of the tweeter is driven by the outer magnet type magnetic circuit, and the diaphragm (diaphragm) for the squawker (middle / low sound) is driven by the inner magnet type magnetic circuit. A frame having an opening in front of the diaphragm (diaphragm) is provided, and the inner and outer magnetic circuits are coaxially arranged on the front surface of the diaphragm, so that the depth direction of a speaker unit, a headphone unit, etc. can be greatly reduced, and the speaker The depth of the device or the headphone device can be reduced, and the magnetomotive force of the magnet of the magnetic circuit can be added to improve the sound quality of the high-frequency speaker unit or the headphone unit.

[Brief description of the drawings]

FIG. 1 is a side sectional view of a speaker unit of the present invention.

FIG. 2 is a side sectional view of the speaker device of the present invention.

FIG. 3 is a side sectional view of the headphone unit of the present invention.

FIG. 4 is an explanatory view of a magnetic path of the magnetic circuit of the present invention.

[Explanation of symbols]

1 Speaker unit, 2 Loudspeaker (tweeter), 3 Loudspeaker (squawker), 6,1
1 ‥‥ magnet, 28 ‥‥ headphone unit, 29
‥‥ Headphone device

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Ryo Yamagishi 6-7-35 Kita-Shinagawa, Shinagawa-ku, Tokyo Inside Sony Corporation (72) Inventor Naotaka Kadota 6-35, Kita-Shinagawa, Shinagawa-ku, Tokyo Sony Corporation F term (reference) 5D012 BA07 BB03 CA06 DA02 DA03 FA02 GA02

Claims (4)

[Claims] 1. A first electro-acoustic conversion means in which a dome-shaped vibrating plate for high sound is pivotably mounted on an external magnetic type magnetic circuit so as to swing forward, and is disposed on a rear surface of the external magnetic type magnetic circuit. A second electric / acoustic conversion means in which a middle / low sound diaphragm is pivotably attached to the back of the provided inner magnetic type magnetic circuit; and the second electric / acoustic conversion means includes the first electric / acoustic conversion means. An electric-to-acoustic converter characterized by comprising electric-to-acoustic converting means arranged coaxially. 2. An electric apparatus comprising: a magnetic circuit disposed in front of a funnel-shaped frame; and a cone-shaped diaphragm disposed behind the frame so as to surround the frame. -Sound conversion device. 3. The electric / acoustic converter according to claim 1, wherein the second low-mid sound diaphragm is formed as a parapolis cone. 4. The electric / acoustic converter according to claim 1, wherein the first and second electric / acoustic converters of the outer magnetic circuit and the inner magnetic circuit are used as a headphone or a speaker. apparatus.