close

Вход

Забыли?

вход по аккаунту

?

DESCRIPTION JP2006148447

код для вставкиСкачать
Patent Translate
Powered by EPO and Google
Notice
This translation is machine-generated. It cannot be guaranteed that it is intelligible, accurate,
complete, reliable or fit for specific purposes. Critical decisions, such as commercially relevant or
financial decisions, should not be based on machine-translation output.
DESCRIPTION JP2006148447
An object of the present invention is to prevent collision between a voice coil bobbin and a
magnetic circuit, and to suppress generation of an unnecessary peak in the vicinity of a high
frequency limit frequency. A first plate is fixed on a pole portion of a frame, a magnet is fixed
thereon, and a second plate is fixed thereon, and an annular yoke is attached to a predetermined
position of a mushroom-like magnetic circuit holder The magnetic circuit holder is fixed on the
second plate via bolts, and the first and second magnetic gaps are formed near the first and
second voice coils, respectively. As a result, even when an excessive input signal is input from the
amplifier side to the first and second voice coil sides, collision of the voice coil bobbin with the
magnetic circuit system and the frame can be prevented. Since the stepped portion having the
upper surface with flatness secured in the direction perpendicular to the vibration direction of
the diaphragm is provided, the strength of the stepped portion decreases and the stiffness of the
neck of the diaphragm decreases and the height of the neck of the diaphragm decreases.
Suppress generation of unnecessary peaks near the frequency band limit frequency. [Selected
figure] Figure 3
Speaker device
[0001]
The present invention relates to the structure of a magnetic circuit or the like in a speaker device.
[0002]
12-04-2019
1
2. Description of the Related Art Conventionally, there is known an external magnet type speaker
device provided with a vibration system having a cone type diaphragm, a voice coil bobbin, a
voice coil and a frame, and a magnetic circuit having a yoke, a magnet and a plate.
As a shape of the cone type diaphragm, a so-called straight shape whose section is linear, a
paracurved shape whose section is bent like a bow, and the like are known.
[0003]
As an example of such a speaker device, for example, a speaker device in which a magnetic
circuit is disposed on the front side (sound output side) of a diaphragm is known (see, for
example, Patent Documents 1 to 3). In these speaker devices (front magnetic circuit system
speaker devices), one magnetic gap is formed between the voice coil bobbin and the magnetic
circuit, and one voice is formed on the voice coil bobbin corresponding to the one magnetic gap.
The coil is wound (1 magnetic gap 1 voice coil system).
[0004]
JP, 2003-299185, A JP, 9-18983, A Patent No. 3412291
[0005]
In the front magnetic circuit speaker device described above, the 1 magnetic gap 1 voice coil
method is adopted.
Therefore, in such a speaker device, there is a problem that the voice coil bobbin and the voice
coil vibrate with large amplitude when excessive input to the voice coil causes the voice coil
bobbin or the voice coil to collide with the frame or the magnetic circuit. .
[0006]
In addition, the front magnetic circuit speaker device using a cone-shaped diaphragm having a
straight shape as described above generally has high high frequency limit frequency (Fh) and
12-04-2019
2
unnecessary high frequency components (peaks) in the vicinity thereof. There is a problem that it
occurs. Therefore, in order to improve such a problem, it is necessary to devise the shape of the
diaphragm. For example, if the cross section of the diaphragm has a paracurved shape, a flat
sound pressure characteristic can be obtained since peaks do not easily occur near the high
frequency limit frequency (Fh). However, in such a speaker device, since the magnetic circuit is
provided on the front side of the diaphragm, there is a limitation in curving the diaphragm to the
sound output side. That is, when a cone-shaped diaphragm having a paracurved shape is used in
such a speaker device, the inner peripheral portion (neck) of the diaphragm is curved toward the
magnetic circuit, so the distance between the diaphragm and the magnetic circuit becomes
smaller. There is a problem that the amplitude margin (amplitude width) in which the diaphragm
vibrates becomes small.
[0007]
Furthermore, in the speaker device according to Patent Document 3 described above, a dustproof
cushion is attached to the neck of the diaphragm in order to enhance the dustproof effect etc.
However, in such a speaker device, the neck (inclined surface) of the diaphragm is made of
adhesive or the like. When attaching a dustproof cushion, there is a problem that an adhesive etc.
will flow to the neck side of a diaphragm at the time of the attachment.
[0008]
As problems to be solved by the present invention, the above-mentioned ones can be mentioned
as an example.
An object of the present invention is to provide a speaker device capable of preventing a collision
between a voice coil bobbin etc. and a magnetic circuit etc. and suppressing an unnecessary high
frequency component (peak) in the vicinity of a high frequency band limit frequency (Fh). Do.
Another object of the present invention is to provide a speaker device capable of preventing the
adhesive from flowing to the neck side of the diaphragm at the time of mounting the buffer
member (including the dustproof function) to the diaphragm. Do.
[0009]
The invention according to claim 1 is a speaker device having a vibration system including a
diaphragm and a magnetic circuit, wherein the magnetic circuit is disposed on the sound output
side of the diaphragm, and a plurality of the magnetic circuits are provided. Wherein the
vibration system includes a voice coil bobbin and a plurality of voice coils wound around the
12-04-2019
3
voice coil bobbin, and in each of the magnetic gaps, each of the corresponding voice coils is
disposed. It is characterized by
[0010]
In one embodiment of the present invention, the speaker device is a speaker device having a
vibration system including a diaphragm and a magnetic circuit, wherein the magnetic circuit is
disposed on the sound output side of the diaphragm, The magnetic circuit has a plurality of
magnetic gaps, and the vibration system has a voice coil bobbin and a plurality of voice coils
wound around the voice coil bobbin, and in each of the magnetic gaps, each of the corresponding
voice coils is It is arranged.
[0011]
In a preferred example, the magnetic circuit includes a first plate, a magnet disposed on the first
plate and magnetized on both sides, a second plate disposed on the magnet, the first plate, the
magnet And yokes opposed to the respective outer peripheral walls of the second plate at regular
intervals.
The plurality of magnetic gaps include a first magnetic gap and a second magnetic gap, the first
magnetic gap being located between the first plate and the yoke, and the second magnetic gap
being It is located between the second plate and the yoke.
Further, the plurality of voice coils include a first voice coil and a second voice coil, the first voice
coil being disposed in the first magnetic gap, and the second voice coil being the second voice
coil. It is disposed in the magnetic gap. That is, this speaker device has a magnetic circuit of a 2
magnetic gap 2 voice coil system. Further, it is preferable that the magnetic field formed in the
first magnetic gap and the magnetic field formed in the second magnetic gap be set in the
opposite direction to each other.
[0012]
In a preferred example, the first voice coil and the second voice coil have the same effective wire
length and are wound in relatively reverse directions, and the first voice coil and the second voice
are It may further comprise a signal supply circuit for supplying the coils with the same and the
12-04-2019
4
same phase electrical signals. In this case, in this speaker device, when an electric signal or the
like of the same same phase is input to the first and second voice coils from the signal supply
circuit side, the voice coil bobbin vibrates and the front side of the diaphragm (sound output side
Sound waves are emitted from). Also, instead of this example, the first voice coil and the second
voice coil have the same effective wire length and are relatively wound in the same direction, and
the first voice coil and the second voice coil may be used. The voice coil may further include a
signal supply circuit that supplies the same and opposite phase electrical signals. In this case, in
this speaker device, when an electric signal or the like in the same and opposite phase is input to
the first and second voice coils from the signal supply circuit side, the voice coil bobbin vibrates
and the front side of the diaphragm (sound output side Sound waves are emitted from).
[0013]
In particular, this speaker device adopts a two magnetic gap two voice coil system. Therefore,
when an excessive input signal is input to the first and second voice coils and the voice coil
bobbin moves with a large amplitude to the sound output side due to some factor, the first voice
coil is positioned in the second magnetic gap. On the other hand, when an excessive input signal
is input to the first and second voice coils and the voice coil bobbin moves with large amplitude
to the side opposite to the sound emission side, the second voice coil is positioned in the first
magnetic gap.
[0014]
In the former case, the first voice coil is influenced by the magnetic field of the second magnetic
gap, and a force (braking force) to move the first voice coil to the opposite side to the sound
emitting side acts on the first voice coil. That is, in this case, since the first voice coil tries to
move to the side opposite to the sound emitting side, the movement of the voice coil bobbin with
large amplitude to the sound emitting side is restricted.
[0015]
On the other hand, in the latter case, the second voice coil is affected by the magnetic field of the
first magnetic gap, and a force (braking force) to move the second voice coil to the sound
emitting side acts on the second voice coil. That is, in this case, since the second voice coil tries to
move to the sound emitting side, the movement of the voice coil bobbin with large amplitude to
12-04-2019
5
the side opposite to the sound emitting side is restricted. As a result, it is possible to suppress the
collision of the voice coil bobbin with the magnetic circuit and the frame opposed thereto.
[0016]
In one aspect of the above speaker device, the vibration system has a frame including a
protrusion that protrudes to the sound output side of the diaphragm, and the magnetic circuit is
disposed on the protrusion and It is accommodated in a space formed on the sound output side
of the diaphragm.
[0017]
According to this aspect, the thickness in the vibration direction of the speaker device can be
reduced, and the speaker device can be thinned accordingly.
[0018]
In a preferred example, the vibration system comprises a support member, such as a magnetic
circuit holder, arranged on the second plate for supporting the yoke.
The support member is preferably formed of a nonmagnetic material.
Further, the support member can include a space in which the voice coil bobbin can move in the
moving direction of the voice coil bobbin. Thereby, the voice coil bobbin can be driven smoothly.
[0019]
In another aspect of the above speaker device, the magnetic circuit may include a yoke, and an
outer peripheral wall of the yoke may be provided with a buffer member having a buffer
function. In a preferred example, the buffer member can be opposed to the diaphragm at a
constant interval. As a result, even if the excessive input signal is input to the first and second
voice coils from the signal supply circuit side and the diaphragm moves to the sound output side
with large amplitude, the buffer member and the diaphragm opposed thereto are Since the
collision occurs, direct collision of the diaphragm and the magnetic circuit can be avoided. In
addition, as a buffer member, the member which has a buffer function, such as a sponge and
12-04-2019
6
urethane, for example is suitable.
[0020]
In another aspect of the above speaker device, the inner circumferential portion of the
diaphragm is provided with a step having a flat surface in the direction perpendicular to the
moving direction of the diaphragm.
[0021]
As a result, when the diaphragm vibrates, the strength in the vibration direction in the step
decreases and the stiffness decreases, so the high frequency limit frequency (Fh) decreases and
unnecessary high frequency components (peak Has an advantage of being able to suppress the
occurrence of (high cut corrugation action).
[0022]
In another aspect of the above speaker device, the flat surface is provided with a buffer member
having a buffer function and having an annular shape.
[0023]
According to this aspect, the flat surface of the step portion is provided with a cushioning
member having a cushioning function and having an annular shape.
That is, since the step has a flat surface, the annular buffer member can be positioned at the
proper position of the diaphragm, and the buffer member can be easily attached to the flat
surface.
Further, when the buffer member is attached to the flat surface of the stepped portion with an
adhesive, the adhesive does not flow to the inner peripheral edge side (neck side) of the
diaphragm.
That is, since the flat surface of the step has flatness, even if the adhesive is applied to the flat
surface of the step, the adhesive remains on the flat surface of the step and the adhesive is the
diaphragm. It does not flow to the inner peripheral edge side (neck side) of Further, the buffer
12-04-2019
7
member also functions as a dustproof member, and dust and the like entering from the sound
output side of the diaphragm can be prevented from entering the inside of the magnetic circuit
and the like from the gap between the upper end of the buffer member and the yoke.
[0024]
In addition, when an excessive input signal is input to the first and second voice coils and the
diaphragm or the like moves with a large amplitude toward the sound output side, the diaphragm
approaches the magnetic circuit side. However, in this case, since the buffer member and the
opposing magnetic circuit come into contact with each other, the collision between the magnetic
circuit and the diaphragm can be prevented. That is, this buffer member has a function as a
cushion member and a dustproof function.
[0025]
Hereinafter, preferred embodiments of the present invention will be described with reference to
the drawings.
[0026]
First Embodiment In the first embodiment, in the speaker device of the front magnetic circuit
system, collisions between the voice coil bobbin etc. and the magnetic circuit etc. are achieved by
providing a plurality of magnetic gaps and voice coils respectively.
[0027]
(Configuration of Speaker Device) FIG. 1 schematically shows a schematic configuration of a
speaker device 100 according to an embodiment of the present invention.
The speaker device 100 can be suitably used as a vehicle-mounted speaker.
FIG. 1 shows a cross-sectional view of the speaker device 100 taken along a plane passing
through the central axis L1. The configuration and the like of the speaker device 100 according
to the first embodiment of the present invention will be described below.
12-04-2019
8
[0028]
The speaker device 100 mainly includes a vibration system 20 having a frame 1, a voice coil
bobbin 2, a damper 3, a voice coil 4, a diaphragm 5, an edge 6 and a magnetic circuit holder 10,
a plate 7, and a magnet as shown in FIG. A magnetic circuit system 30 having the yoke 8 and the
yoke 9 and buffer members 12, a plurality of tinsel wires 13, a plurality of terminal members 17,
a bolt 14 and a name plate 15 as various other members are provided. The speaker device 100 is
a front magnetic circuit type speaker device having a magnetic circuit system 30 on the front
surface side (sound output side) of the diaphragm 5.
[0029]
First, each component of the vibration system 20 will be described.
[0030]
Various components of the speaker device 100 are fixed to the frame 1, and the frame 1 serves
to support the components.
The frame 1 has a pole portion 1a and a flange portion 1b extending outward from the lower end
portion of the outer peripheral wall of the pole portion 1a with a predetermined inclination. The
pole part 1a (protrusion part) protrudes in the sound emission side of the diaphragm 5
mentioned later. A through hole 1 ac for inserting a bolt 14 is formed substantially at the center
of the upper end portion of the pole portion 1 a. An annular protrusion 1ad projecting toward
the sound output side is formed near the approximate center of the top surface of the pole
portion 1a. The annular projection 1ad has a function of positioning a first plate 7a described
later at an appropriate position on the pole portion 1a. On the other hand, a circular recess 1ab is
formed at the lower end of the pole portion 1a. In the recess 1 ad, a name plate 15 which has a
circular shape and on which a trade name and product information and the like are printed is
attached.
[0031]
The flange portion 1 b has a substantially cup-like cross-sectional shape. Further, the flange
12-04-2019
9
portion 1 b has a first flat portion 1 ba and a second flat portion 1 bb, and the upper surface
thereof secures flatness. The first flat portion 1ba is formed at a position near the center of the
flange portion 1b. An outer peripheral edge portion of a damper 3 described later is attached
onto the first flat portion 1ba. Moreover, the several terminal member 17 is attached on 1st flat
part 1ba. The second flat portion 1bb is formed at the upper end portion of the flange portion 1b.
On the second flat portion 1bb, an outer peripheral edge portion of an edge 6 described later is
attached.
[0032]
The voice coil bobbin 2 has a substantially cylindrical shape. The first voice coil 4a is wound
around the outer peripheral wall of the voice coil bobbin 2 corresponding to the vicinity of the
upper end portion of the pole portion 1a, and the second voice coil 4b is wound around the
upper end portion of the outer peripheral wall of the voice coil bobbin 2 ing. For this reason, the
first voice coil 4 a and the second voice coil 4 b are wound around the outer peripheral wall of
the voice coil bobbin 2 at a constant interval. Further, the winding direction of the first voice coil
4 a with respect to the voice coil bobbin 2 and the winding direction of the second voice coil 4 b
with respect to the voice coil bobbin 2 are opposite to each other. Furthermore, the effective wire
length of the first voice coil 4a and the effective wire length of the second voice coil 4b are the
same.
[0033]
Each of the first voice coil 4a and the second voice coil 4b has one set of plus / minus lead wires
(not shown). The lead wire on the positive side is an input wiring of the L (or R) channel signal,
and the lead wire on the negative side is an input wiring of the ground (GND: ground) signal. The
respective lead wires are electrically connected to one end side of each tinsel wire 13 drawn to
the front side (sound output side) of the diaphragm 5, and the other end side of each tinsel wire
13 is a frame It is electrically connected to the one end side of each terminal member 17 located
on the 1st flat part 1ba of one. Further, the other end side of each of the terminal members 17 is
electrically connected to the corresponding input wiring on the amplifier side. Therefore, to the
first voice coil 4a and the second voice coil 4b, through the respective terminal members 17, the
respective tinsel wires 13, the respective lead wires and the like, electric signals of the same and
the same phase from the signal supply circuit on the amplifier side Each signal is input.
[0034]
12-04-2019
10
The damper 3 has a substantially annular shape, and has an elastic portion in which a corrugated
shape is formed concentrically. The outer peripheral edge of the damper 3 is fixed on the first
flat portion 1 ba of the frame 1, while the inner peripheral edge of the damper 3 is fixed to the
lower end of the outer peripheral wall of the voice coil bobbin 2.
[0035]
Various materials such as paper-based, polymer-based, and metal-based can be applied to the
diaphragm 5 in accordance with various applications. The diaphragm 5 is a cone-shaped
diaphragm, and is formed in a so-called paracurved shape in which the cross section is bent in a
bow shape. The inner peripheral edge portion of the diaphragm 5 is attached at a position near
the inner peripheral edge portion of the damper 3 and at a position near the lower end portion of
the outer peripheral wall of the voice coil bobbin 2.
[0036]
The edge 6 has a substantially semicircular cross-sectional shape. The inner peripheral edge
portion of the edge 6 is fixed to the lower surface side of the outer peripheral portion of the
diaphragm 5, and the lower surface of the outer peripheral edge portion of the edge 6 is fixed on
the second flat portion 1bb of the frame 1.
[0037]
The magnetic circuit holder 10 is formed of a nonmagnetic material, has a mushroom shape, and
has a protrusion 10a, a cylindrical portion 10b and a gap 10c.
[0038]
The protrusion 10a has a substantially cylindrical shape and protrudes toward the second plate
7b described later.
At substantially the center of the lower surface of the protrusion 10a, an annular protrusion
12-04-2019
11
10ab is formed which protrudes to the side of the magnet 8 described later. A screw hole 10 ac
for fixing the bolt 14 is formed substantially at the center of the protrusion 10 a and the annular
protrusion 10 ab. The cylindrical portion 10 b has a substantially cylindrical shape. The inner
diameter of the cylindrical portion 10b corresponding to the approximate center of the
cylindrical portion 10b to the vicinity of the upper end thereof is smaller than the inner diameter
of the cylindrical portion 10b corresponding to the approximate center of the cylindrical portion
10b to the vicinity of the lower end thereof. For this reason, a step-like stepped portion 10ba
(step portion) is formed substantially at the center of the inner peripheral wall of the cylindrical
portion 10b. Further, a gap 10c is formed between the inner peripheral wall of the cylindrical
portion 10b and the outer peripheral wall of the projection 10a. The gap 10c is a space for the
voice coil bobbin 2 to move. The lower end portion of the inner peripheral wall of the cylindrical
portion 10b is formed with a cutout portion 10bb formed by cutting out a portion of the inner
peripheral wall. For this reason, a space is formed between the notch 10bb and the belowdescribed yoke 9 opposed thereto.
[0039]
Next, each component of the magnetic circuit system 30 will be described.
[0040]
The plate 7 has a first plate 7a and a second plate 7b in a substantially annular shape.
The inner peripheral wall of the first plate 7a is in contact with the outer peripheral wall of the
annular projection 1ad, and the lower surface of the first plate 7a is fixed to the upper surface of
the pole portion 1a. Thus, the first plate 7a is mounted on the pole portion 1a in a state where
the first plate 7a is positioned at an appropriate position on the pole portion 1a. The magnet 8
has an annular shape and is fixed on the first plate 7a. Both surfaces (upper surface and lower
surface) of the magnet 8 are magnetized to one of the S pole and the N pole. The second plate 7
b is fixed on the magnet 8 at a position corresponding to the first plate 7 a. The first plate 7 a,
the magnet 8 and the second plate 7 b are accommodated in the voice coil bobbin 2.
[0041]
The yoke 9 has a substantially annular shape and has an inner diameter larger than the outer
diameter of the voice coil bobbin 2. The yoke 9 is fixed to the step portion 10 ba of the
12-04-2019
12
cylindrical portion 10 b and the inner circumferential wall of the cylindrical portion 10 b located
below the step portion 10 ba in the drawing. Thus, the yoke 9 is supported by the magnetic
circuit holder 10. A buffer member 12 having an annular shape is attached to a part of the outer
peripheral wall of the yoke 9. That is, the buffer member 12 is attached to the lower end portion
of the outer peripheral wall of the yoke 9 in a state where a portion of the upper surface is
positioned on a portion of the lower surface 10bc of the cylindrical portion 10b. The buffer
member 12 has a role of preventing the diaphragm 5 from coming into direct contact with the
magnetic circuit meter 30 when an electric signal with a large amplitude is input. The reason for
attaching the buffer member 12 at such a position is that the magnetic circuit system 30 or the
diaphragm 5 and the buffer member 12 make contact (interference) when the diaphragm 5
moves based on an appropriate electrical signal or the like. It is to prevent. As the buffer member
12, for example, a member having a buffer function such as urethane or sponge is preferable.
[0042]
The magnetic circuit holder 10 to which the yoke 9 having the above configuration is attached is
fixed on the second plate 7 b. Specifically, the annular projection 10ab of the magnetic circuit
holder 10 is inserted into the opening of the second plate 7b, and the outer peripheral wall of the
annular projection 10ab is in contact with the inner peripheral wall of the second plate 7b. . And,
a part of the lower surface of the protrusion 10a is in contact with the second plate 7b. Further,
bolts 14 are inserted into the respective openings of the pole portion 1a of the frame 1, the first
plate 7a, the magnet 8 and the second plate, and the tip of the bolt 14 is fixed to the screw hole
10ac of the projection 10a. It is done. Thus, the magnetic circuit holder 10 to which the yoke 9 is
attached is fixed on the second plate 7b. Further, in such a state, the vicinity of the upper end
portion of the inner peripheral wall of the yoke 9 is opposed to the outer peripheral wall of the
second plate 7b and the magnet 8 with a constant gap, and a gap (second magnet A gap 16b) is
formed. On the other hand, the lower end portion of the inner peripheral wall of the yoke 9 is
opposed to the outer peripheral wall of the first plate 7a and the magnet 8 at a constant distance,
and a gap (first magnetic gap 16a) is formed between them. It is formed. That is, the magnetic
circuit system 30 includes the first magnetic gap 16a and the second magnetic gap 16b, and the
first voice coil 4a and the second voice coil 4b corresponding to each of them (two magnetic gaps
and two voices). Coil system). In the magnetic circuit system 30, the magnetic flux of the magnet
8 is concentrated on the second magnetic gap 16b and the first magnetic gap 16a. More
specifically, in the magnetic circuit system 30, a magnetic path (magnetic field) of magnet 8 →
first plate 7a → first magnetic gap 16a → yoke 9 → second magnetic gap 16b → second plate 7b
→ magnet 8 The first plate 7a and the first magnetic gap 16a are equivalent to the second plate
7b and the second magnetic gap 16b, and the order may be changed and read. Further, in the
magnetic circuit system 30, the direction of the magnetic field formed in the vicinity of the first
plate 7a, the magnet 8 and the yoke 9 is the direction of the magnetic field formed in the vicinity
12-04-2019
13
of the second plate 7b, the magnet 8 and the yoke 9. And the opposite relationship, but this point
will be described later.
[0043]
In the speaker device 100 described above, the electric signal output from the amplifier side is
output to the first voice coil 4a and the second voice coil 4b through the terminal members 17,
the tinsel wires 13 and the lead wires. Ru. As a result, driving forces are generated in the same
direction and in the same direction in the first voice coil 4a in the first magnetic gap 16a and in
the second voice coil 4b in the second magnetic gap 16b. It vibrates in the axial direction. Thus,
the speaker device 100 emits a sound wave in the direction of the arrow Y1.
[0044]
(Configuration of Magnetic Circuit System) Next, with reference to FIG. 2, the configuration and
the like of the magnetic circuit system 30 characterizing the present invention will be described.
In addition, since the configuration of the magnetic circuit system 30 has been described above,
the following description will be focused on a portion having the features of the present
invention. FIG. 2 shows an enlarged sectional view of a portion of the broken line area E1 in FIG.
[0045]
As described above, the present invention is characterized in that the magnetic circuit system 30
of the two magnetic gap and two voice coil system is adopted.
[0046]
That is, the first magnetic gap 16 a is formed between the outer peripheral wall of the first plate
7 a and the vicinity of the lower end portion of the inner peripheral wall of the yoke 9.
Then, the first voice coil 4a is wound around the outer peripheral wall of the voice coil bobbin 2
corresponding to the vicinity of the upper end of the pole portion 1a, and the first voice coil 4a is
disposed at the position corresponding to the first magnetic gap 16a. It is done. Here, the first
voice coil 4a is wound clockwise when the speaker device 100 is observed from the direction
12-04-2019
14
opposite to the direction of the arrow Y1 in FIG. A magnetic field (a magnetic field near the first
magnetic gap 16a) formed in the vicinity of the first plate 7a, the magnet 8 and the yoke 9 is
generated in the direction of the arrow Y10. On the other hand, a second magnetic gap 16 b is
formed between the outer peripheral wall of the second plate 7 b and the vicinity of the upper
end portion of the inner peripheral wall of the yoke 9. A second voice coil 4b is wound in the
vicinity of the upper end portion of the outer peripheral wall of the voice coil bobbin 2, and the
second voice coil 4b is disposed at a position corresponding to the second magnetic gap 16b.
Here, the second voice coil 4b is wound counterclockwise when the speaker device 100 is
observed from the direction opposite to the arrow Y1 direction in FIG. 1, and the winding
direction is the winding direction of the first voice coil 4a. And the opposite is. A magnetic field (a
magnetic field near the second magnetic gap 16b) formed in the vicinity of the second plate 7b,
the magnet 8, and the yoke 9 is generated in the direction of the arrow Y11 (opposite to the
direction of the arrow Y10). In the present invention, the direction of the magnetic field
generated near the first magnetic gap 16a may be set in the arrow Y11 direction, and the
direction of the magnetic field generated near the second magnetic gap 16b may be set in the
arrow Y10 direction. Furthermore, the effective wire length of the second voice coil 4b is set to
be the same as the effective wire length of the first voice coil 4a. According to the above
configuration, the first voice coil 4a and the second voice coil 4b can be moved with the same
force and in the same direction.
[0047]
That is, in the speaker device 100, when the same voice signal of the same phase and the same
phase is supplied to the first voice coil 4a and the second voice coil 4b from the amplifier side,
the voice coil bobbin 2 vibrates in the directions of arrows Y2 and Y3. Do. At this time, the upper
end side of the voice coil bobbin 2 moves in the gap 10c of the magnetic circuit holder 10 in the
directions of the arrows Y2 and Y3.
[0048]
Here, if an excessive input signal is input to the voice coil 4 due to some factor, the voice coil
bobbin 2 vibrates with large amplitude in the directions of the arrows Y2 and Y3. That is,
assuming that an excessive input signal is input to the voice coil 4 and the voice coil bobbin 2 is
moved with large amplitude in the direction of arrow Y3, the lower end portion of the second
voice coil 4b is located in the first magnetic gap 16a. It will be. Thereby, since the second voice
coil 4b is affected by the magnetic field in the first magnetic gap 16a, a force (a braking force) in
the direction of arrow Y2 acts on the second voice coil 4b according to Fleming's left hand rule. .
12-04-2019
15
That is, since the second voice coil 4b tries to move in the direction of the arrow Y2 at this time,
the movement of the voice coil bobbin 2 with large amplitude in the direction of the arrow Y3 is
restricted. As a result, the voice coil bobbin 2 moves with large amplitude in the direction of
arrow Y3, and it is possible to prevent the lower end portion of the voice coil bobbin 2 from
colliding with the frame 1 opposed thereto (see also FIG. 1).
[0049]
On the other hand, assuming that an excessive input signal is input to the voice coil 4 and the
voice coil bobbin 2 is moved with large amplitude in the direction of arrow Y2, the upper end
portion of the first voice coil 4a is located in the second magnetic gap 16b. It will be. As a result,
the first voice coil 4a is affected by the magnetic field in the second magnetic gap 16b, and a
force (braking force) in the direction of arrow Y3 acts on the first voice coil 4a according to
Fleming's left hand rule. That is, at this time, since the first voice coil 4a tries to move in the
arrow Y3 direction, the movement of the voice coil bobbin 2 with a large amplitude in the arrow
Y2 direction is restricted. Thereby, the voice coil bobbin 2 can be moved with large amplitude in
the direction of the arrow Y2, and the upper end portion of the voice coil bobbin 2 and the
magnetic circuit holder 10 opposed thereto can be prevented from colliding (see also FIG. 1) .
[0050]
As described above, since the speaker device 100 according to the first embodiment employs the
magnetic circuit system 30 of the two magnetic gap and two voice coil system, an excessive input
signal from the signal supply circuit on the amplifier side to the voice coil 4 side Can be
suppressed, the collision between the voice coil bobbin 2 and the magnetic circuit system 30, the
frame 1, and the magnetic circuit holder 10 can be suppressed. In addition, the diaphragm 5
having a so-called paracurved shape is applied to the speaker device 100. That is, as shown in
FIG. 2, the cross-sectional shape of the diaphragm 5 is curved so as to be convex on the sound
output side. For this reason, when an excessive input signal is input to the voice coil 4 side, the
diaphragm 5 moves with large amplitude in the direction of the arrow Y2, so that a part of the
upper surface of the diaphragm 5; The yoke 9 and the magnetic circuit holder 10 facing each
other easily collide with each other.
[0051]
12-04-2019
16
In this respect, in the speaker device 100 according to the first embodiment, the buffer member
12 having a buffer function is provided in the vicinity of the lower end portion of the outer
peripheral wall of the yoke 9. Therefore, when the diaphragm 5 moves with a large amplitude in
the direction of the arrow Y2, the lower end portion of the buffer member 12 comes in contact
with a part of the upper surface of the diaphragm 5 opposed thereto. That is, in this case, the
diaphragm 5 is moved to, for example, the position of the diaphragm 5x indicated by the
alternate long and short dash line, and the lower end portion of the buffer member 12 and a part
of the upper surface of the diaphragm 5 opposed thereto are in contact It will be done. As a
result, it is possible to avoid direct collision of part of the upper surface of the diaphragm 5 with
the yoke 9 and the cylindrical portion 10b of the magnetic circuit holder 10 opposed thereto.
Therefore, the diaphragm 5 and the like can be prevented from being damaged.
[0052]
Further, in the speaker device 100 according to the first embodiment, the magnetic circuit
system 30 is disposed on the pole portion 1a of the frame 1, and the magnetic circuit system 30
is formed on the upper surface side (sound output side) of the diaphragm 5. It is designed to be
housed in a As a result, the magnetic circuit system 30 can be prevented from protruding more
than necessary from the upper end of the diaphragm 5, and as shown in FIG. 1, the distance D1
in the vibration direction of the speaker device 100 can be reduced. . That is, thinning of the
speaker device 100 can be achieved.
[0053]
In the speaker device 100 according to the first embodiment, since the diaphragm 5 having a
paracurved shape is applied as described above, unnecessary high frequency components (peaks)
are generated in the vicinity of the high frequency band limit frequency (Fh). Flat sound pressure
characteristics can be obtained without.
[0054]
[Second Embodiment] In the second embodiment, similarly to the first embodiment, in the
speaker device of the front magnetic circuit system, a voice coil bobbin etc. and a magnetic
circuit etc. are provided by respectively providing a plurality of magnetic gaps and voice coils. To
prevent collisions.
12-04-2019
17
In addition, in the second embodiment, the inner peripheral portion (neck portion) of the
diaphragm is provided with a stepped portion having an upper surface ensuring flatness. As a
result, unnecessary high frequency components (peaks) in the vicinity of the high frequency
band limit frequency (Fh) can be suppressed, and attachment of a buffer member having a buffer
function and a dustproof function can be facilitated.
[0055]
Next, the configuration and the like of the speaker device 200 according to the second
embodiment will be described with reference to FIGS. 3 and 4. In the following, the same
elements as those of the speaker device 100 according to the first embodiment are given the
same reference numerals, and the description thereof is omitted. FIG. 3 shows a cross-sectional
view of the speaker device 200 according to the second embodiment, taken along a plane
passing through the central axis L1. FIG. 4 shows a partial cross-sectional view corresponding to
the broken line area E3 in FIG.
[0056]
The configuration of the speaker device 200 according to the second embodiment is substantially
the same as the configuration of the speaker device 100 according to the first embodiment.
However, when the two are compared, the two differ in the structure of the diaphragm 5, the
shape of the cylindrical portion 10 b of the magnetic circuit holder 10, the mounting position of
the buffer member 12, and the method of drawing the tinsel wire 13. In particular, the speaker
device 200 according to the second embodiment is characterized in the structure of the
diaphragm 5.
[0057]
Specifically, in the speaker device 200 according to the second embodiment, a stepped portion
5a (step) is formed in the vicinity of the inner peripheral portion (neck) of the diaphragm 5. The
upper surface 5ab of the stepped portion 5 has flatness. The buffer member 12 is attached to the
upper surface 5ab of the step portion 5a via an adhesive (not shown). That is, in the first
embodiment, the buffer member 12 is attached to the outer peripheral wall of the yoke 9, but in
the second embodiment, the buffer member 12 is attached to the upper surface 5ab of the step
portion 5a of the diaphragm 5. . Further, by attaching the buffer member 12 to the upper surface
12-04-2019
18
5ab of the step portion 5a, in the second embodiment, one end side of the plurality of tinsel wires
13 is located below the step portion 5a of the diaphragm 5 and the diaphragm 5 is It is made to
draw out to the upper surface side (sound emission side). One end side of each tinsel cord 13 is
electrically connected to each lead wire (not shown) of the corresponding first voice coil 4a and
second voice coil 4b.
[0058]
In addition, although a notch 10bb formed by notching a part of the inner peripheral wall of the
cylindrical portion 10b in the magnetic circuit holder 10 is formed as compared with the notch
10bb of the first embodiment. The size of the notch is increasing. Thus, the space formed
between the notch 10bb of the second embodiment and the outer peripheral wall of the yoke 9 is
larger than that of the first embodiment. The reason for doing this is as follows. As described
above, in the second embodiment, the buffer member 12 is provided not on the side of the
magnetic circuit system 30 but on the top surface 5 ab of the step portion 5 a of the diaphragm
5. Therefore, when the diaphragm 5 is moved in the arrow Y 2 direction, the buffer member 12
is also moved in the same direction accordingly. At this time, when the buffer member 12 collides
with the cylindrical portion 10b of the magnetic circuit holder 10 opposed to the buffer member
12, an appropriate sound wave can not be emitted. Therefore, in the second embodiment, the size
of the notch of the notch 10bb in the second embodiment is set to the first embodiment so that
the both do not collide when driven based on an appropriate electrical signal or the like. It is
larger than that of the example. That is, it is to prevent interference between the upper end
portion of the buffer member 12 and the cylindrical portion 10a opposed thereto when the
diaphragm 5 or the like moves based on an appropriate electrical signal or the like.
[0059]
The speaker device 200 described above has the following effects.
[0060]
First, since the speaker apparatus 200 according to the second embodiment adopts the two
magnetic gap and two voice coil system as in the first embodiment, even when an excessive input
signal is input to the voice coil 4 side. The collision of the voice coil bobbin 2 with the magnetic
circuit system 30, the frame 1, and the magnetic circuit holder 10 can be suppressed.
[0061]
12-04-2019
19
Further, in the speaker device 200 according to the second embodiment, the stepped portion 5 a
having the upper surface 5 ab, in which flatness is secured, is provided in the vicinity of the inner
peripheral portion of the diaphragm 5.
Thereby, while being able to position the buffer member 12 which makes an annular shape in the
appropriate position of the diaphragm 5, the buffer member 12 can be easily attached to the
upper surface 5ab.
Further, when the buffer member 12 is attached to the upper surface 5ab of the step portion 5a
with an adhesive, the adhesive does not flow to the inner peripheral edge side of the diaphragm
5. That is, since the upper surface 5ab of the stepped portion 5a has flatness, even if the adhesive
is applied to the upper surface 5ab of the stepped portion 5a, the adhesive remains on the upper
surface 5ab of the stepped portion 5a and the adhesive Does not flow to the inner peripheral
edge side of the diaphragm 5. Further, since the annular buffer member 12 is attached to the
upper surface 5ab of the step portion 5a, the space formed between the buffer member 12, the
yoke 9, the first voice coil 4a, the voice coil bobbin 2 and the diaphragm 5 is It is in a nearly
closed state. Therefore, dust or the like coming from the sound output side of the diaphragm 5,
that is, from the direction of the arrow Y5 shown in FIG. 3 is from the gap between the upper end
of the buffer member 12 and the cylindrical portion 10b of the yoke 9 Can be prevented from
invading
[0062]
Here, if the buffer member 12 and the yoke 9 come into contact with each other when the
speaker device 200 is driven, an appropriate sound wave can not be emitted. Therefore, between
the upper end of the inner peripheral wall of the buffer member 12 and the lower end of the
outer peripheral wall of the yoke 9 There are some gaps in the.
[0063]
Also, as shown in FIG. 4, assuming that an excessive input signal is input to the voice coil 4 and
the diaphragm 5 etc. is moved with large amplitude in the direction of arrow Y2, the diaphragm
5 in the solid position in the stationary state is , And moves to the position of the diaphragm 5x
indicated by an alternate long and short dash line.
12-04-2019
20
At this time, the vicinity of the inner peripheral portion of the diaphragm 5 approaches the lower
end portion of the yoke 9 and the lower end portion side of the cylindrical portion 10 b of the
magnetic circuit holder 10. However, in this case, the cushioning member 12 in the solid line
position in the stationary state also moves to the position of the cushioning member 12x
indicated by the alternate long and short dash line, and the cushioning member 12x and the
lower end of the cylindrical portion 10b of the magnetic circuit holder 10 opposed thereto
Contact with the unit. Thereby, it is possible to prevent direct collision of the yoke 9 and the
magnetic circuit holder 10 with a part of the upper surface of the diaphragm 5 opposed thereto.
Therefore, the diaphragm 5 and the like can be prevented from being damaged. That is, the
buffer member 12 of the second embodiment has both a buffer function as a cushion member
and a dustproof function.
[0064]
Further, as described above, the step portion 5 a is formed on the inner peripheral portion of the
diaphragm 5. In particular, the upper surface 5ab of the stepped portion 5a is formed to have
flatness in the direction perpendicular to the vibration direction (the directions of arrows Y2 and
Y3) of the diaphragm 5. As a result, when the speaker device 200 is driven, generation of
unnecessary high frequency components (peaks) in the vicinity of the high frequency band limit
frequency (Fh) can be prevented.
[0065]
This point will be described in comparison with the acoustic characteristics of the speaker device
according to the comparative example. FIG. 5 is a graph showing the acoustic characteristics of
the speaker device 200 according to the second embodiment when the sound pressure level
(SPL: Sound Pressure Level) is set on the vertical axis and the frequency (Hz) is set on the
horizontal axis. . In FIG. 5, graph W1 shows fundamental wave characteristics, graph W2 shows
second harmonic distortion characteristics, and graph W3 shows third harmonic distortion
characteristics. FIG. 6 is a graph showing acoustic characteristics of the speaker device according
to the comparative example corresponding to FIG. FIG. 6 is a graph measured under the same
conditions as the present invention. Further, in FIG. 6, a graph W11 shows a fundamental wave
characteristic, a graph W12 shows a second harmonic distortion characteristic, and a graph W13
shows a third harmonic distortion characteristic.
[0066]
12-04-2019
21
In addition, although illustration of the speaker apparatus which concerns on a comparative
example is abbreviate | omitted, the structure is as follows roughly. That is, the speaker device
according to the comparative example adopts the front magnetic circuit method and the 1
magnetic gap 1 voice coil method (generally, the method in which the second voice coil 4b and
the like are removed in FIG. 1). Has a straight shape, and no stepped portion is formed on the
inner periphery thereof.
[0067]
As shown by W1 in FIG. 5, in the speaker device 200 of the second embodiment, a flat sound
pressure level is obtained in a band of about 180 Hz to about 3 KHz. Further, in the speaker
device 200, as indicated by W1 in FIG. 5, the high frequency limit frequency (Fh) is
approximately 4 KHz, and the sound pressure level of the high frequency limit frequency (Fh) is
approximately 36 It is about dB). The high frequency band limit frequency Fh refers to a
frequency when the vibration of the voice coil bobbin 7 or the like is not transmitted to the
diaphragm 5 side. On the other hand, in the speaker device according to the comparative
example, as indicated by W11 in FIG. 6, a flat sound pressure level is obtained in the band of
about 180 Hz to about 3 KHz, as in the speaker device 200 of the second embodiment. . In the
speaker device according to the comparative example, as indicated by W11 in FIG. 6, the high
frequency limit frequency (Fh) is about 7.5 KHz and the sound pressure level of the high
frequency limit frequency (Fh) Is about 37 (dB).
[0068]
Here, the acoustic characteristics of the speaker device 200 according to the second embodiment
and the speaker device according to the comparative example are compared.
[0069]
As described above, while the high limit frequency (Fh) of the speaker device 200 according to
the second embodiment is about 4 KHz, the high limit frequency (Fh) of the speaker device
according to the comparative example is about It is about 7.5 KHz.
Therefore, in the speaker device 200 according to the second embodiment, the high frequency
12-04-2019
22
limit frequency (Fh) is smaller than that in the comparative example. Further, in the second
embodiment and the comparative example, as shown by the broken line area E5 in FIG. 5 and the
broken line area E6 in FIG. It is happening. As can be understood by comparing the sizes of the
respective peaks, the speaker device 200 according to the second embodiment has a smaller
peak as an unnecessary high-frequency component as compared with the comparative example.
The reason will be further described. In general, the high frequency limit frequency (Fh) in the
speaker device is represented by the following formula: Fh = 1 / 2π√ {(1 / m1) + (1 / m2)} ×
Sn (Expression 1) Here, "m1" is the mass (Kg) of the voice coil 4, "m2" is the mass (Kg) of the
diaphragm, and "Sn" is the stiffness (N / m) of the inner peripheral portion (neck) of the
diaphragm. Are shown respectively.
[0070]
In the second embodiment, the step portion 5 a is provided on the inner peripheral portion
(neck) of the diaphragm 5. In particular, the upper surface 5ab of the stepped portion 5a is
formed to have flatness in the direction perpendicular to the vibration direction of the diaphragm
5, as described above. Therefore, when the diaphragm 5 vibrates, the strength in the vibration
direction (directions of arrows Y2 and Y3 in FIG. 4) in the stepped portion 5a decreases, and the
stiffness Sn in the above equation 1 decreases. As a result, the high frequency band limit
frequency (Fh) in the above equation 1 is lowered, and generation of unnecessary high frequency
components (peaks) in the vicinity thereof can be suppressed (high cut corrugation action). On
the other hand, in the speaker device according to the comparative example, since the diaphragm
having a straight cross section is used, a peak is easily generated in the vicinity of the high
frequency limit frequency (Fh).
[0071]
Further, when the graph W2 of the second harmonic distortion of the second embodiment and
the graph W12 of the second harmonic distortion of the comparative example are compared, the
second harmonic distortion of the second embodiment is about 100 Hz or more. In the band, it is
smaller than the second harmonic distortion of the comparative example. Further, the
relationship between the third harmonic distortion of the second embodiment and the third
harmonic distortion of the comparative example is also the same. That is, when the graph W3 of
the third harmonic distortion of the second embodiment and the graph W13 of the third
harmonic distortion of the comparative example are compared, the third harmonic distortion of
the second embodiment is about 100 Hz or more. In the band, it is smaller than the third
harmonic distortion of the comparative example. This is because the magnetic circuit system 30
12-04-2019
23
adopts a two magnetic gap two voice coil system. That is, in the magnetic circuit system 30, the
winding direction of the first voice coil 4a on the voice coil bobbin 2 and the winding direction of
the second voice coil 4b on the voice coil bobbin 2 are opposite to each other. This is because the
self inductance on the first voice coil 4a side and the self inductance on the second voice coil 4b
side are canceled (cancelled).
[0072]
[Modifications] In the first and second embodiments described above, the winding direction of
the first voice coil 4a on the voice coil bobbin 2 and the winding direction of the second voice
coil 4b on the voice coil bobbin 2 are reversed and identical to each other. And it was made to
input the electric signal etc. of the same phase. However, according to the present invention, the
winding direction of the first voice coil 4a on the voice coil bobbin 2 and the winding direction of
the second voice coil 4b on the voice coil bobbin 2 are the same direction, and each has the same
and opposite phases. An electrical signal or the like may be input. Also in this case, the effects of
the present invention can be obtained.
[0073]
BRIEF DESCRIPTION OF THE DRAWINGS Sectional drawing of the speaker apparatus based on
1st Example of this invention. The fragmentary sectional view which expanded magnetic circuit
system vicinity which concerns on 1st Example. Sectional drawing of the speaker apparatus
based on 2nd Example of this invention. The fragmentary sectional view which expanded
magnetic circuit system vicinity which concerns on 2nd Example. The graph which shows the
acoustic characteristic of the speaker apparatus which has a diaphragm which concerns on 2nd
Example. The graph which shows the acoustic characteristic of the speaker apparatus which has
a diaphragm concerning a comparative example.
Explanation of sign
[0074]
1 frame 2 voice coil bobbin 4a first voice coil 4b second voice coil 5 diaphragm 5a stepped
portion 7a first plate 7b second plate 8 magnet 9 yoke 10 magnetic circuit holder 16a first
magnetic gap 16b second magnetic gap 12 buffer member 20 vibration system 30 magnetic
circuit system 100, 200 speaker device
12-04-2019
24
12-04-2019
25
Документ
Категория
Без категории
Просмотров
0
Размер файла
41 Кб
Теги
description, jp2006148447
1/--страниц
Пожаловаться на содержимое документа