JP2940587B2 - Speaker vibration detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speaker vibration detecting device, and more particularly to a speaker vibration detecting device suitable for performing high-fidelity reproduction of a speaker output of a sound reproducing system.

[0002]

2. Description of the Related Art Conventionally, a speaker vibration detecting device which detects vibration displacement or acceleration of a vibration system of a speaker and improves the output characteristics of the speaker by feeding back the detection signal to a speaker driving circuit is shown in FIGS. Many were provided.

In FIG. 10, reference numeral 3 denotes a diaphragm for a speaker;
Is a suspension and 5 is a frame. Reference numeral 30 denotes a yoke forming a magnetic circuit of the speaker, and 31 denotes a voice coil bobbin. A voice coil 32 is wound around a predetermined position of the voice coil bobbin 31. Reference numeral 33 denotes a dust cap, and reference numeral 34 denotes a piezoelectric element installed substantially at the center of the dust cap 33.

The loudspeaker thus configured is a voice coil.
A vibrating system that vibrates when a signal current supplied to the vibrator 32 flows, that is, a voice coil bobbin 31, a diaphragm 3 having an inner diameter bonded to the voice coil bobbin 31, and a dust cap 33 bonded to the diaphragm 3 Vibrate in proportion to the signal current.

The piezoelectric element 34 attached to the dust cap 33 of the vibration system generates an electric signal in proportion to the vibration displacement of the dust cap 33, and detects the change in the output of the piezoelectric element 34 to change the vibration of the speaker. The vibration displacement of the system was detected.

The electrical signal proportional to the vibration displacement of the speaker detected in this way is fed back to the speaker drive circuit, compared with the input signal originally supplied to the speaker drive circuit, and is generated in the speaker vibration system. An error signal can be extracted.

By synthesizing the error signal with the input signal, an output signal from a speaker driving circuit that cancels an error component generated in the vibration system of the speaker can be obtained. By driving the voice coil 32 of the loudspeaker, high-fidelity reproduction was performed.

FIG. 11 shows another conventional example. In the figure, reference numeral 35 denotes a microphone (hereinafter simply referred to as a microphone). The microphone 35 is attached to a speaker frame 5 by a fixture 36 attached to the speaker frame 5. The dust cap 33 is installed so as to be located near the center of the front surface of the dust cap 33.

The microphone 35 installed in this way can output an electric signal proportional to the vibration displacement of the vibration system of the speaker according to the sound pressure level received from the diaphragm 3 of the speaker.
By returning this electric signal to the speaker drive circuit, high-fidelity reproduction is performed as described above.

[0010]

However, in the above-described conventional vibration displacement detecting device for a vibration system of a speaker, since the voice coil 32 is surrounded by a magnetic circuit, the installation position of the vibration detecting element is limited. However, there is a disadvantage that an optimum detection device cannot be mounted at an optimum detection position.

Originally, it is desirable to detect the vibration displacement of the vibration system of the speaker by directly detecting the vibration displacement of the voice coil 32, as in the conventional example, in the vicinity of the piezoelectric element 34 attached to the dust cap 33 or the dust cap 33. When detecting with a microphone 35, etc., installed in the loudspeaker, it is difficult to accurately obtain the vibration displacement of the vibration system of the speaker due to air intervening between the detection element and the vibration system, the bending of the dust cap 33, etc. In addition, sufficient accuracy could not be obtained.

The present invention has been made in view of the above points, and an object of the present invention is to enable a vibration displacement of a vibration system of a speaker to be detected at an optimum position and by an optimum detection method. Another object of the present invention is to provide a speaker vibration detecting device with high vibration detection accuracy which has solved the disadvantages of the conventional example.

[0013]

SUMMARY OF THE INVENTION A speaker vibration detecting apparatus according to the present invention has a magnetic circuit in which two magnets are arranged so as to oppose each other with a magnetic material interposed therebetween to form a repulsive magnetic field. And a detecting means for detecting a vibration displacement of a vibration system of the speaker, wherein a detection signal from the detecting means is fed back to a speaker driving circuit. An optical sensor installed outside the circuit, and the optical sensor is installed such that a detection light beam path of the optical sensor is positioned on an extension of a vibration displacement direction of the vibration system.

A speaker having a magnetic circuit in which two magnets are arranged so as to be of the same polarity with a magnetic material interposed therebetween to form a repulsive magnetic field, and detects a vibration displacement of a vibration system of the speaker. In a speaker vibration detecting device having a detecting means and returning a detection signal from the detecting means to a speaker driving circuit, a detection light path of the optical sensor is positioned in a direction perpendicular to a vibration displacement direction of the vibration system. The above-mentioned optical sensor is installed in such a manner.

Further, the optical sensor has a detector having a light emitting element and a light receiving element, a light reflecting member for receiving and reflecting an irradiation light beam from the detector, and a light reflecting member for reflecting the light beam from the light reflecting member. The light reflecting member is installed on the outer peripheral portion of the voice coil, the lower end portion of the voice coil, the inner peripheral back side of the diaphragm, or the inner peripheral back side of the suspension, and the detector reflects the light reflected by the light reflecting member. It is installed on a speaker frame facing the member or a holder for fixing a magnetic circuit.

Also, a detector in which the optical sensor has a light emitting element and a light receiving element, a light reflecting member having a line pattern for receiving and reflecting an irradiation light beam from the detector, And a detector for receiving the light reflected from the reflection member, wherein the line pattern light reflection member is installed on the outer periphery of the voice coil, and the detector is installed on a speaker frame at a position facing the line pattern light reflection member. You may.

Further, the optical sensor comprises a light emitting portion having a light emitting element and a light receiving portion having a light receiving element, wherein the light emitting portion is a voice coil outer peripheral portion, a voice coil lower end portion, or a vibration coil. The light receiving unit is installed on the inner peripheral back side of the board or the inner peripheral back side of the suspension, and the light receiving unit is installed on a speaker frame facing the light emitting unit or a holder for fixing a magnetic circuit.

Further, the wiring of the power supply to the optical sensor installed on the outer peripheral portion of the voice coil, the lower end portion of the voice coil, the back side of the diaphragm, or the back side of the suspension is mounted so as to follow the shape of the suspension. It uses a conductive member.

[0019]

According to the present invention, an optical sensor is used as detecting means for detecting a vibration displacement of a vibration system of a speaker. The optical sensor has a light emitting element and a light receiving element. A light reflecting member for receiving and reflecting the irradiated light beam, and detecting the reflected light beam from the light reflecting member with the detector to detect the vibration displacement of the vibration system.

The light reflecting member is provided at the lower end of the voice coil of the yoke in which the repulsive magnetic field is formed, at the back side near the inner diameter of the diaphragm, or at the back side near the inner diameter of the suspension. The detector is positioned on an extension of a vibration displacement direction of a vibration system such as the voice coil, in which a detection light path of an irradiation light beam from an element and a reflection light beam from the light reflection member is further positioned relative to the light reflection member. The detector is installed on the speaker frame or the holder that fixes the magnetic circuit at the facing position.

As described above, the irradiation light from the light emitting element of the detector installed on the extension of the vibration displacement direction is efficiently reflected by the light reflecting member, and the reflected light is accurately received by the light receiving element of the detector. You. Since the light reflecting member performs the same vibration as the vibration of the voice coil and the like, the intensity of the light reflected from the light reflecting member changes due to a change in the distance between the detector and the light reflecting member. By detecting the intensity of the light beam, the detector can detect the vibration displacement of the voice coil.

Further, it is also possible to detect a signal proportional to the vibration speed of the voice coil or the like by utilizing the Doppler effect of the light reflected by the light reflecting member.

The detection signal of the vibration displacement or the detection speed signal detected in this way is fed back to the speaker driving circuit, and is subtracted from the input signal for driving the speaker, so that the difference signal from the input signal generated by the speaker vibration system is obtained. That is, an error signal can be calculated, and by adding an inverted signal of the error signal to the speaker drive signal, a speaker drive signal in which the error signal has been canceled can be obtained. It can be carried out.

Further, as another vibration detecting device, a line pattern light reflecting member is installed on the outer periphery of the voice coil, and a reflected light path from the line pattern light reflecting member is positioned in a direction perpendicular to the vibration displacement direction of the voice coil. A detector is installed on the frame at the opposing position, and the light beam reflected by the line pattern light reflecting member is received to detect the vibration displacement of the voice coil.

By irradiating an irradiation light beam from the light emitting element of the detector to the line pattern light reflecting member that performs the same vibration as the voice coil, and detecting the number of lines by the reflected light beam of the vibrating line pattern light reflecting member, The vibration displacement of the voice coil can be accurately detected.

As another vibration detecting device, the optical sensor comprises a light emitting section having a light emitting element, and a light receiving section having a light receiving element, wherein the light emitting section is formed by a repulsive magnetic field. Coil lower end, or diaphragm back side,
Alternatively, the light receiving section is installed on the back side of the suspension, and the light receiving section is installed on a speaker frame or a holder opposite to the light emitting section, and the irradiation light from the light emitting element of the light emitting section is received by the light receiving element of the light receiving section. However, when a light emitting section is installed on the back side of the diaphragm, it is necessary to form a passage hole through which the light emitted from the light emitting section passes at a predetermined position of the suspension.

[0027] The distance between the light-emitting portion that performs the same vibration as that of the voice coil and the like and the fixed light-receiving portion is increased or decreased due to the vibration displacement of the voice coil, and the Doppler effect is used. Vibration displacement can be detected by detecting the effect of increasing or decreasing the wavelength of the received light beam.

As described above, the detected vibration displacement signal is supplied to the speaker drive circuit in the same manner as described above, and the error signal generated in the vibration system is canceled in the same manner as described above, so that the speaker output can be reproduced with high fidelity. .

Further, the power supply to the light emitting portion and the like installed on the outer peripheral portion of the voice coil or the lower end portion of the voice coil is performed by a tinsel wire of a conductive member mounted so as to follow the shape of the suspension directly adhered to the voice coil. By supplying the power from the power supply or the like, power supply wiring and the like become easy.

[0030]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a speaker vibration detecting apparatus according to the present invention will be described with reference to FIGS. The same parts as those in the conventional example are denoted by the same reference numerals, and description thereof will be omitted. FIG. 1 shows a first embodiment of the present invention, and is a half sectional view of a speaker in which a vibration detecting device is attached to a lower end of a voice coil on an extension of a vibration displacement direction of the voice coil.

FIG. 2 shows a second embodiment of the present invention, and a half sectional view of a speaker having a vibration detecting device attached to the lower end of a diaphragm. FIG. 3 shows a third embodiment of the present invention. FIG. 6 is a half sectional view of a speaker having a vibration detection device attached to a lower end of the speaker. FIG. 4 shows a fourth embodiment of the present invention, and is a half sectional view of a speaker in which another vibration detecting device is attached to a lower end of a voice coil.

FIG. 5 shows a fifth embodiment of the present invention, in which a half of a speaker having a vibration detecting device mounted on a side surface of an outer peripheral portion of a voice coil in a direction perpendicular to the vibration direction of the voice coil. FIG. 6 is a sectional view showing a sixth embodiment of the present invention, and is a half sectional view of a speaker in which another vibration detecting device is mounted in a direction perpendicular to the vibration direction of the voice coil in the same manner as described above.

FIG. 7 is an enlarged perspective view showing a vibration detecting device according to the fifth embodiment of the present invention in which a line pattern light reflecting member is attached to an outer peripheral portion of the voice coil, and FIG. 8 is a tinsel wire attached to the voice coil and a suspension. FIG. 9 is a block diagram showing a speaker driving circuit.

In the first embodiment shown in FIG. 1, reference numeral 1 denotes a yoke of a repulsive magnetic circuit composed of two magnets having the same polarity and a center plate made of a magnetic material, and 2 denotes a voice coil. The coil 2 is formed in a bobbin-less shape, and an inner peripheral portion of the diaphragm 3 or the suspension 4 is directly fixed to an outer peripheral portion of the voice coil 2 with an adhesive or the like.

Reference numeral 6 denotes a holder for fixing a magnet or the like of the yoke 1.
Attached to. Reference numeral 7 denotes a light reflecting member, which is fixed to the lower end of the voice coil 2 with an adhesive or the like. Reference numeral 8 denotes a detector, which has a function of emitting and receiving light rays, is attached to the holder 6 immediately below the light reflecting member 7, and forms a vibration detecting device with the light reflecting member 7 and the detector 8. Make up. Reference numeral 9 denotes a light beam emitted by the light emitted from the detector 8, and further shows a reflected light beam reflected by the light reflecting member 7 and input to the detector 8.

In FIG. 9, reference numeral 20 denotes an input terminal of a speaker input signal, and reference numeral 21 denotes a speaker drive circuit. The speaker drive circuit 21 has a subtractor 22 to which an input signal is supplied and a differential amplifier 23, An amplifier 24 amplifies the output of the differential amplifier 23. Reference numeral 25 denotes a speaker. The speaker 25 includes a speaker unit 26 and a vibration detecting device 27 attached to the speaker unit 26.

The vibration detecting device 27 of the loudspeaker 25 configured as described above detects a vibration displacement of the voice coil 2 which is a vibration system of the loudspeaker by an optical sensor function. That is, the light reflecting member 7 attached to the lower end of the voice coil 2 performs the same vibration as the vibration of the voice coil 2, and a light emitting element (not shown) provided on the detector 8 with respect to the vibrating light reflecting member 7. Irradiating light 9 from the first detector 8) and is reflected toward a light receiving element (not shown) of the detector 8.

The intensity of the reflected light beam 9 changes depending on the distance between the detector 8 and the vibrating light reflecting member 7. By detecting the intensity of the reflected light beam 9, the vibration displacement of the voice coil 2 is converted into a voltage signal. Can be detected.

As another detection method, in order to obtain a signal proportional to the vibration speed of the voice coil 2, the light reflecting member 7 is used.
Doppler effect of the reflected light 9 due to the vibration of The vibration displacement of the voice coil 2 can be detected by the movement of the voice coil 2 in a certain direction.

As described above, since the detector 8 is provided with the light emitting element and the light receiving element, a certain size is required. Since the periphery is a magnetic circuit using a repulsive magnetic field, there is no magnetic circuit as seen in a general speaker, and the installation of the detector 8 is extremely easy.

That is, the irradiation light 9 from the detector 8 described above
Can be easily mounted so that the direction of the vibration is in the same direction as the direction of vibration displacement of the voice coil 2, and the reflected light beam 9 can be efficiently reflected by the light reflecting member 7. Displacement can be detected.

As described above, the vibration displacement or vibration speed of the voice coil 2 detected by the detector 8 is converted into acceleration, and this acceleration signal is fed back to the subtracter 22 of the speaker drive circuit 21. On the other hand, an input signal for driving the speaker 25 is supplied from the input terminal 20 to the subtractor 22, and the input signal and the acceleration signal are compared and subtracted to extract a difference component error signal.

That is, the error signal is a signal component in which the input signal and the vibration of the voice coil 2 are not the same, that is, a difference component. This error signal is the inverted input of the differential amplifier 23 constituted by the operational amplifier circuit. It is supplied to the terminal (-). on the other hand,
The non-inverting input terminal (+) of the differential amplifier 23 is connected to the input terminal 20.
The error signal and the input signal are combined and supplied to the speaker unit 26 via the amplifier 24.

Since the synthesized speaker driving signal is synthesized with the input signal by inverting the error signal generated by the vibration of the voice coil 2, the synthesized speaker driving signal becomes a signal for canceling the error signal. By applying the drive signal to the speaker unit 26, the speaker output from the speaker 25 cancels the error signal, and a reproduced output more faithful to the input signal can be obtained.

In the second embodiment shown in FIG. 2, reference numeral 4a denotes a through hole provided on the suspension 4 through which the irradiated / reflected light beam 9 passes. The same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

In the second embodiment, the light reflecting member 7 is mounted near the inner diameter portion on the back side of the diaphragm 3 of the speaker vibration system.
The detector 8 is attached to the holder 6 or the frame 5 directly below the light reflecting member 7 to constitute a vibration detecting device.

The end of the inner diameter of the diaphragm 3 is a directly driven diaphragm 3 which is directly bonded to the outer periphery of the voice coil 2. The vibration of the unit 26 can be detected.

As described above, the detector 8 installed immediately below the light reflecting member 7 fixed to the diaphragm 3 is located on an extension of the vibration displacement direction, and the irradiation light 9 from this detector 8
Is incident on the light reflecting member 7 through a through hole 4 a provided in the suspension 4, and the reflected light beam 9 reflected by the light reflecting member 7 is input to the detector 8 in the same manner as described above.

The vibration displacement of the loudspeaker can be detected by the light emitting element and the light receiving element of the detector 8 in the same manner as in the first embodiment. Thus, high-fidelity reproduction can be performed using the speaker 25.

The detector 8 can be easily mounted in the same manner as described above. Further, since the light reflecting member 7 is mounted on the diaphragm 3, it can be mounted more easily than the lower end of the voice coil 2. Can be processed.

The third embodiment shown in FIG. 3 uses a light reflecting member 7 and a detector 8 which are the same vibration detecting devices as described above, and
The light reflecting member 7 is attached near the inner diameter portion on the back side of the suspension 4, and the detector 8 is attached to the holder 6 or the frame 5 directly below the light reflecting member 7.

The suspension 4 is composed of the voice coil 2
Since the vibration of the voice coil 2 is directly propagated, the vibration displacement equivalent to the vibration of the voice coil 2 can be detected from the vibration of the suspension 4.

That is, the irradiation light beam 9 from the detector 8 is reflected by the light reflecting member 7 attached to the suspension 4, and the reflected light beam 9 is incident on the detector 8 to detect the vibration displacement of the suspension 4. This detection signal is fed back to the speaker drive circuit 21 to cancel the error signal of the vibration system and perform reproduction with higher fidelity than the speaker 25 in the same manner as described above. In addition, the light reflecting member 7 and the detector 8 can be easily attached in the same manner as described above, and accurate vibration displacement detection can be performed.

The fourth embodiment shown in FIG. 4 uses a vibration detecting device in which a light-emitting element and a light-receiving element are provided independently of each other. In the drawing, reference numeral 10 denotes a light-emitting element. The light emitting unit 10 is mounted on the lower end of the voice coil 2. Reference numeral 11 denotes a light receiving unit having a light receiving element. The light receiving unit 11 is attached to the holder 6 and receives the irradiation light beam 12 from the light emitting unit 10. The same parts as those in the first embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

In FIG. 8, reference numeral 2a denotes a voice coil 2;
A winding start terminal 2a formed of, for example, a copper foil or the like is provided on the outer peripheral portion of the voice coil 2. The winding start terminal 2a of the voice coil 2 is connected to the winding start terminal 2c by soldering. Reference numeral 2b denotes a winding terminator provided on the outer peripheral portion of the voice coil 2 and formed of, for example, copper foil or the like.
Are connected by soldering.

Reference numeral 4a denotes a corrugation formed on the suspension 4. Reference numeral 19 denotes a tinsel wire woven in a flat knitted shape. The inner ends 19a of the two tinsel wires 19 are connected to the winding start terminal 2a and the winding terminal 2b by soldering.

Reference numerals 10a and 10b denote power supply terminals for supplying the light-emitting elements of the transmission section 10. These power supply terminals 10a and 10b are further supplied with power by the above-mentioned two separate tinsel wires. It can be in the operating state.

The light emitting unit 10 of the vibration detecting device for a loudspeaker thus constructed is attached to the lower end of the voice coil 2.
The same vibration is performed in accordance with the vibration of the voice coil 2. When the oscillating light emitting unit 10 is activated and irradiated with the irradiation light beam 12, the irradiation light beam 12 can be received by the light receiving unit 10 located on an extension of the voice coil 2 in the vibration displacement direction.

That is, the vibrating light emitting unit 10 is a fixed light receiving unit.
Since the irradiation light beam 12 is irradiated with the distance interval being increased or decreased with respect to 11, the light receiving unit 10 can detect the vibration speed by the Doppler effect of the received irradiation light beam 12.

As described above, the vibration speed signal obtained by detecting the vibration displacement of the voice coil 2 is fed back to the speaker drive circuit 21, and as described above, the error component of the reproduction output of the speaker 25 is canceled to perform high-fidelity reproduction. be able to. Moreover, the light emitting unit 10 and the light receiving unit having a certain size
Even if it is 11, since it is a speaker unit 25 employing a repulsive magnetic circuit, a mounting space is secured and mounting can be performed without any problem. The mounting position of the light receiving unit 11 is the same as the vibration displacement direction of the voice coil 2. By using the same direction, more accurate vibration displacement detection is possible.

FIG. 5 shows a fifth embodiment, in which a voice coil 2 is wound around a predetermined lower portion of a voice coil bobbin, and a diaphragm 3 and a suspension 4 are adhesively bonded to the upper portion of the voice coil bobbin.

In FIG. 5, reference numeral 13 denotes a line pattern light reflecting member attached to the outer peripheral portion of the voice coil 2, and reference numeral 14 denotes a light emitting element and a light receiving element.
13 is a detector attached to the frame 5 located at a right angle to 13.

In FIG. 7, reference numeral 13a denotes a plurality of line patterns formed on the surface of the line pattern light reflecting member 13, and the line pattern 13a is formed in a direction perpendicular to the vibration displacement direction of the voice coil 2. . 14a is the detector 14
The power terminal 14b is provided with a mounting hole.

When power is supplied from a power supply line (not shown) wired through the frame 5 to the detector 14 of the speaker vibration detecting device thus configured, the built-in light emitting element is activated. Irradiation light 15 is emitted. The irradiation light beam 15 irradiates the line pattern light reflection member 13 and is reflected. The reflected light beam 15 is incident on the detector 14 and received by the built-in light receiving element.

The line pattern light reflecting member 13 vibrates in the same vibration displacement direction in accordance with the vibration of the voice coil 2, and the irradiation light 15 of the detector 14 is irradiated from the direction perpendicular to the vibrating line pattern light reflecting member 13. When irradiated, the light is reflected by the irradiated light beam 15 while traversing the line pattern 13a.

When this reflected light beam 15 hits the black portion of the line pattern 13a, the reflected light beam 15 is weak, and when it hits the white portion without the line pattern 13a, the reflected light beam 15
15 is reflected intensely, the strength of the reflected light beam 15 is detected, and how many times the strength is changed, that is, the vibration displacement amount of the voice coil 2 can be measured by detecting the number of lines due to vibration. .

The detection data of the amount of vibration displacement detected by the detector 14 is fed back to the speaker drive circuit 21, and as described above, the error signal of the speaker reproduction output can be canceled to obtain a high-fidelity reproduction output.

Since the detector 14 can be installed at right angles to the direction of vibration displacement of the voice coil 2, the irradiation light 15 from the detector 14 can be efficiently reflected by the line pattern light reflecting member 13. Yes, voice coil 2
The accuracy of detecting the amount of vibration displacement can be improved. In addition, since the line pattern light reflecting member 13 can be formed to be extremely thin and lightweight, an extremely reliable vibration displacement can be detected with almost no load on the voice coil 2 side. .

FIG. 6 shows a sixth embodiment.
Reference numeral 16 denotes a light-emitting unit having a light-emitting element attached to the outer peripheral portion of the voice coil 2; It is. Reference numeral 18 denotes a light beam emitted from the light emitting unit 16.

The light emitting section 16 of the vibration detecting device thus configured
Performs the same vibration as the vibration displacement of the voice coil 2 in the same manner as described above, and the irradiation light beam 18 from the light emitting section 16 also vibrates in proportion to the vibration. The oscillating light beam 18 is applied to the voice coil 2
The amount of vibration displacement of the voice coil 2 can be detected by receiving light with a plurality of light receiving elements built in the light receiving unit 17 installed in parallel with the vibration displacement direction of the voice coil 2.

The vibration displacement amount data thus detected is fed back to the speaker drive circuit 21 in the same manner as described above, and the speaker output can be made a high-fidelity reproduction output. Also,
The light emitting unit 16 can be a lightweight one attached to the voice coil 2 and the light receiving unit 17 can be arranged at right angles to the vibration displacement direction of the voice coil 2, so that a highly reliable vibration displacement can be detected as described above.

The power supply to the light emitting section 16 is the fourth power supply.
Power can be supplied by the tinsel wire 19 provided on the suspension 4 in the same manner as in the embodiment.

As described above, the vibration detecting device is configured by using the pair of detectors and the light reflecting member or the light emitting unit and the light receiving unit to detect the vibration displacement of the vibration system. By using this, it is also possible to detect the vibration displacement of each of the vibration systems of the speaker such as the divided diaphragm.

[0074]

As described in the first to sixth embodiments, the vibration detecting device for a speaker according to the present invention has a light reflecting member or a light emitting portion directly on a voice coil, a diaphragm, or a suspension. Since the light reflecting member and the like can be reduced in weight, the weight load of the voice coil is hardly applied.

On the other hand, since the detector and the light receiving section are installed on a holder or the like extending in the direction of the vibration displacement of the vibration system, in a parallel direction, or at a right angle, and the like, the vibration displacement is detected. There is an effect that vibration displacement can be detected.

Further, since the vibration detecting device is incorporated in the magnetic circuit using the repulsive magnetic field to detect the vibration displacement of the vibration system, a sufficient space for mounting the vibration detecting device can be obtained, and the mounting operation of the vibration detecting device is easy. In addition, there is an effect that the position can be accurately determined and the efficiency of the speaker manufacturing process is improved.

Further, it has excellent features such as simple structure and easy implementation because it can be constructed at low cost.

[Brief description of the drawings]

FIG. 1 is a first embodiment of a vibration detecting device according to the present invention;
FIG. 6 is a half sectional view of a speaker in which a vibration detecting device is attached to a lower portion of a voice coil according to the embodiment.

FIG. 2 is a half sectional view of a speaker in which a vibration detecting device is attached to a lower portion of a diaphragm according to a second embodiment.

FIG. 3 is a half sectional view of a speaker in which a vibration detecting device is attached to a lower portion of a suspension according to a third embodiment.

FIG. 4 is a half sectional view of a speaker in which another vibration detecting device is attached below a voice coil according to a fourth embodiment.

FIG. 5 is a half sectional view of a speaker according to a fifth embodiment to which another vibration detection device is attached in a direction perpendicular to the vibration displacement direction of the voice coil.

FIG. 6 is a half sectional view of a speaker according to a sixth embodiment in which another vibration detecting device is mounted in a direction perpendicular to a voice coil.

FIG. 7 is an enlarged perspective view showing a vibration detection device in which a line pattern light reflecting member is attached to an outer peripheral portion of a voice coil.

FIG. 8 is a perspective view showing a connection wiring state between a light emitting unit or a voice coil winding start / end terminal of the vibration detection device and a tinsel wire attached to a suspension.

FIG. 9 is a block diagram showing a speaker driving circuit.

FIG. 10 is a cross-sectional view of a speaker showing a conventional vibration detection device.

FIG. 11 is a cross-sectional view of a speaker showing another conventional vibration detection device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Yoke of repulsive magnetic field 2 Voice coil 2a Winding start terminal of voice coil 2b Voice coil winding terminal 2c Voice coil winding end 2d Voice coil winding end 3 Reference Signs List 5 Frame 6 Holder 7 Light reflecting member 8 Detector 9 Irradiated or reflected light 10 Light emitting unit with light emitting element 10a, 10b Power supply terminal of light emitting unit 11 Light receiving unit with light receiving element 12 Irradiated light 13 Line pattern light reflecting member 13a Line pattern 14 Detector 15 Irradiated or reflected light 16 Light-emitting part with light-emitting element 17 Light-receiving part with light-receiving element 18 Irradiation light 19 Kinshi wire 19a attached to suspension 19a End of inner diameter of Kinshi wire 20 Input signal input terminal 21 Speaker drive circuit 22 Subtractor 23 Differential amplifier 24 Amplifier 25 Speaker 26 Speaker unit 27 Vibration detector

──────────────────────────────────────────────────続 き Continuation of the front page (51) Int.Cl. ⁶ identification code FI H04R 29/00 310 H04R 29/00 310 (58) Field surveyed (Int.Cl. ⁶ , DB name) H04R 3/04 101 G01H 9/00 H04R 9/02 102 H04R 9/04 102 H04R 29/00 310

Claims (6)

(57) [Claims] 1. A speaker having a magnetic circuit in which two magnets are arranged so as to be of the same polarity with a magnetic material interposed therebetween to form a repulsive magnetic field, and a vibration displacement of a vibration system of the speaker is detected. A vibration detecting device for a loudspeaker having a detecting means, wherein a detection signal from the detecting means is fed back to a loudspeaker driving circuit, wherein the detecting means comprises an optical sensor installed outside a magnetic circuit of the loudspeaker; A vibration detecting device for a loudspeaker, wherein the optical sensor is installed so that a light path is positioned on an extension of a vibration displacement direction of the vibration system. 2. A loudspeaker having a magnetic circuit in which two magnets are arranged so as to be of the same polarity with a magnetic material interposed therebetween to form a repulsive magnetic field, and a vibration displacement of a vibration system of the loudspeaker is detected. In a speaker vibration detecting device having a detecting means and returning a detection signal from the detecting means to a speaker driving circuit, a detection light path of the optical sensor is positioned in a direction perpendicular to a vibration displacement direction of the vibration system. A vibration detecting device for a speaker, wherein the optical sensor is installed as described above. 3. A detector in which the optical sensor has a light emitting element and a light receiving element, a light reflecting member for receiving and reflecting an irradiation light beam from the detector, and a light reflecting member from the light reflecting member. The light reflecting member is installed on the outer peripheral portion of the voice coil, the lower end portion of the voice coil, the inner peripheral back side of the diaphragm, or the inner peripheral back side of the suspension, and the detector reflects the light reflected by the light reflecting member. The speaker vibration detecting device according to claim 1, wherein the speaker vibration detecting device is provided on a speaker frame facing a member or a holder for fixing a magnetic circuit. 4. A detector in which the optical sensor has a light emitting element and a light receiving element, a light reflecting member having a line pattern for receiving and reflecting an irradiation light beam from the detector, And a detector for receiving the light reflected from the reflection member, wherein the line pattern light reflection member is installed on the outer periphery of the voice coil, and the detector is installed on a speaker frame at a position facing the line pattern light reflection member. 3. The apparatus according to claim 2, wherein the vibration is detected. 5. The optical sensor according to claim 1, wherein the optical sensor includes a light emitting unit having a light emitting element, and a light receiving unit having a light receiving element.
The light emitting unit is installed on an outer peripheral portion of a voice coil, a lower end portion of a voice coil, an inner peripheral back side of a diaphragm, or an inner peripheral back side of a suspension, and the light receiving unit is positioned at a position opposite to the light emitting unit. 3. The speaker vibration detecting device according to claim 1, wherein the device is mounted on a holder for fixing a circuit. 6. The wiring of the power supply to the optical sensor installed on the outer peripheral portion of the voice coil, the lower end portion of the voice coil, the back side of the diaphragm, or the back side of the suspension is mounted along the shape of the suspension. The speaker vibration detecting device according to claim 5, wherein the vibration detecting device is formed using a conductive member. "is.