TECHNICAL FIELD
[0001] The present invention relates to a suspension structure for a high power micro speaker
and, more particularly, to a shape of a suspension which ensures a lightweight of
the suspension as well as high reliability and a conductive pattern which applies
electric signals.
BACKGROUND ART
[0002] Sound reproduction techniques of mobile multimedia have been improved with the development
of mobile communication technologies, as a result of which high performance, high
sound quality and high power are required of a micro speaker.
[0003] In most cases, a conventional micro speaker does not use a special suspension to
ensure a lightweight of a diaphragm and connects a lead wire of a voice coil to the
diaphragm via bonding to apply external electric signals to the voice coil. Therefore,
unbalanced vibration is often generated due to the absence of the suspension, and
the lead wire of the coil is often down in high power due to a tensile force, which
makes it difficult for the micro speaker to be applied to high power.
[0004] In order to solve the foregoing problem, there has been developed a micro speaker
using a suspension provided with a conductive pattern for transmitting electric signals.
In the case of the micro speaker using the suspension, an increase in weight of the
diaphragm, which results from the use of the suspension, leads to a decrease in sound
pressure of the micro speaker. In addition, cracks may occur in the conductive pattern
in high power, causing a defect.
[0005] FIG. 1 is a view showing a shape of a voice coil and a lead wire used in a conventional
suspension type micro speaker, FIG. 2 is a view showing fabrication of a rectangular
coil of FIG. 1, and FIG. 3 is a view showing a shape of a suspension used in the conventional
micro speaker. As illustrated in FIG. 2, a circular voice coil 10 is changed to a
rectangular voice coil 20 using a jig 30. Here, lead wires 22 and 24 of the voice
coil 20 are positioned on the short side of the rectangular shape. Referring to FIG.
3, a suspension 40 includes an outer peripheral portion 42, an inner peripheral portion
46, and a connection portion 44 connecting the outer peripheral portion 42 to the
inner peripheral portion 46. A conductive pattern 50 as well as land portions 60 for
use in soldering or bonding the lead wires 22 and 24 of the voice coil 20 are formed
on the surface of the suspension 40. In the conventional suspension 40, the land portions
60 for use in soldering or bonding the lead wires 22 and 24 of the voice coil 20 are
formed on the connection portion 44 disposed on the short side adjacent to the positions
of the lead wires 22 and 24 of the coil.
[0006] FIG. 4 is a view showing stress distribution of each portion that is generated in
the event of vibration of the conventional suspension.
[0007] Here, it can be seen that a significant surface tension occurs inside the short connection
portion 44 disposed on the short side of the suspension 40, as a result of which cracks
may easily occur in the conductive pattern 50 formed on the surface of the suspension
40.
DISCLOSURE OF THE INVENTION
[0008] An object of the present invention is to provide a suspension structure which can
resist high power in a micro speaker.
[0009] Another object of the present invention is to provide a conductive pattern of a suspension
for a micro speaker which can transmit electric signals even when cracks occur in
some part of the suspension.
[0010] A further object of the present invention is to provide a shape of a suspension and
a conductive pattern which can minimize a further decrease in sound pressure caused
by the use of the suspension.
[0011] A still further object of the present invention is to provide a suspension which
does not interrupt a smooth vertical movement of a diaphragm.
[0012] According to an aspect of the present invention, there is provided a suspension for
a high power micro speaker that includes an outer peripheral portion, a central portion
and a connection portion, is provided with a conductive pattern, and is formed in
a rectangular shape, wherein land portions for use in soldering or welding lead-in
wires of a voice coil are formed on long connection portions disposed on long sides.
[0013] In some embodiments, protective films for protecting the conductive suspension are
attached to the outer peripheral portion, the central portion and the connection portion,
and some parts of the protective films attached to the long connection portions disposed
on the long sides are removed.
[0014] In some embodiments, protective film for protecting the conductive suspension is
attached to the outer peripheral portion, the central portion and the connection portion,
and the protective film on the long connection portions disposed on the long sides
is removed.
[0015] In some embodiments, protective film for protecting the conductive suspension is
attached to the outer peripheral portion, the central portion and the connection portion,
and some part of the protective film on the central portion is removed.
[0016] In some embodiments, protective film for protecting the conductive suspension is
attached to the outer peripheral portion, the central portion and the connection portion,
and some parts of the protective film on short connection portions disposed on short
sides are removed.
[0017] According to another aspect of the present invention, there is provided a high power
micro speaker which includes a conductive suspension described above, and a voice
coil, lead-in wires of which corresponding in direction to land portions of the suspension.
[0018] According to a further aspect of the present invention, there is provided a high
power micro speaker which includes a conductive suspension described above, and a
voice coil, lead-in wires of which being drawn out from opposite diagonal positions
and shaped in a right-angle direction.
[0019] In the conductive suspension for high power provided by the present invention, the
land portions for use in soldering or welding the lead-in wires of the voice coil
are disposed on the long connection portions positioned in a short direction, which
prevents cracks from occurring in the conductive pattern in the event of high power
vibration, and the land portions are symmetrically positioned, which prevents unbalanced
vibration.
[0020] Moreover, in the conductive suspension provided by the present invention, some parts
of the protective films on the long connection portions positioned in a short direction
are removed to reduce the intensity of vertical vibration, which facilitates low sound
vibration when the speaker is mounted.
[0021] Additionally, in the conductive suspension provided by the present invention, some
part of the protective film on the central portion of the suspension is removed to
improve a sound pressure.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022]
FIG. 1 is a view showing a shape of a voice coil and a lead wire used in a conventional
micro speaker having a suspension.
FIG. 2 is a view showing fabrication of a rectangular coil of FIG. 1.
FIG. 3 is a view showing the suspension used in the conventional micro speaker.
FIG. 4 is a view showing stress distribution of each portion that is generated in
the event of vibration of the conventional suspension.
FIG. 5 is a view showing a voice coil lead-in wire structure provided in a micro speaker
according to a first embodiment of the present invention.
FIG. 6 is a view showing positions of land portions of a suspension for the high power
micro speaker according to the first embodiment of the present invention.
FIG. 7 is a view showing the position, from which a protective film is removed, on
the suspension for the high power micro speaker according to the first embodiment
of the present invention.
FIGS. 8 to 10 are views showing a high power micro speaker according to a second embodiment
of the present invention.
BEST MODE FOR CARRYING OUT THE INVENTION
[0023] Hereinafter, preferred embodiments of the present invention will be described in
detail with reference to the accompanying drawings.
[0024] FIG. 5 is a view showing a voice coil lead-in wire structure provided in a high power
micro speaker according to a first embodiment of the present invention. A voice coil
100 provided in the high power micro speaker according to the first embodiment of
the present invention is formed in a rectangular shape like a conventional rectangular
coil 10. However, the voice coil 100 provided in the high power micro speaker of the
present invention and the voice coil 10 of the prior art have a difference in drawing-out
directions of lead wires 120 and 140. The lead wires 120 and 140 of the voice coil
100 are not disposed on the same side of the rectangular shape side by side but drawn
out from opposite diagonal sides. Preferably, the lead wires 120 and 140 are drawn
out from ends of two longer sides among the four sides of the rectangle. These positions
are adjacent to the positions of land portions of the suspension for the high power
micro speaker according to the first embodiment of the present invention and are easy
to weld or solder the lead wires 120 and 140 to the land portions, as will be discussed
later. Meanwhile, after drawn out, the lead wires 120 and 140 of the voice coil 100
are shaped in a right-angle direction according to a shape of a connection portion
of the suspension discussed later.
[0025] FIG. 6 is a view showing the suspension for the high power micro speaker according
to the first embodiment of the present invention. A suspension 200 according to the
first embodiment of the present invention includes an outer peripheral portion 210,
connection portions 220' and 220" and a central portion 230, and also includes a terminal
portion 240 for providing electric connection to an external terminal on one side.
In addition, a conductive pattern 250 is formed on the suspension 200, in particular,
on the outer peripheral portion 210, the terminal portion 240 on one side of the outer
peripheral portion 210, and the connection portions 220' and 220". Meanwhile, the
suspension 200 is formed in a rectangular shape, and land portions 260 for use in
welding or soldering the lead wires 120 and 140 of the voice coil 100 are disposed
on the connection portions 220' (longer sides of the rectangle) connecting the outer
peripheral portion 210 to the central portion 230 among the connection portions 220'
and 220". That is, the land portions 260 for use in welding or soldering the lead
wires 120 and 140 are symmetrically positioned in a diagonal direction. The land portions
260 for use in welding or soldering the lead wires 120 and 140 of the voice coil 100
are disposed on the longer connection portions 220' among the connection portions
220' and 220", which prevents cracks from occurring in the conductive pattern 250
in high power, and the land portions 260 are symmetrically positioned, which prevents
unbalanced vibration.
[0026] FIG. 7 is a view showing the position, from which a protective film is removed, on
the suspension for the high power micro speaker according to the first embodiment
of the present invention. Protective films 310, 320 and 330 for protecting the conductive
pattern 250 formed on the suspension 200 as well as the suspension 200 itself are
attached to the top and bottom of the suspension for the high power micro speaker
according to one embodiment of the present invention. The protective films 310, 320
and 330 are attached to the outer peripheral portion 210, the connection portions
220' and 220", and the central portion 230 of the suspension 200. Some sections 320',
320" and 330' of the protective films 310, 320 and 330 attached to the top of the
suspension 200 (where the voice coil 100 is not attached) are removed to improve sound
characteristics of the high power micro speaker. The sections 320', 320" and 330',
from which the protective films are removed, are designated as shaded sections in
FIG. 7.
[0027] In particular, the protective films 320 attached to the longer connection portions
220' disposed on the long sides among the connection portions 220' and 220" of the
suspension 200 are partially or wholly removed (320') to reduce the intensity of vertical
vibration, which facilitates low sound vibration when the speaker is mounted.
[0028] Additionally, the protective films 320 attached to the connection portions 220" disposed
on the short sides among the connection portions 220' and 220" of the suspension 200
are partially removed (320") to reduce the intensity of vertical vibration, which
facilitates low sound vibration when the speaker is mounted.
[0029] Moreover, the central portion of the protective film 330 attached to the central
portion 230 of the suspension 200 is partially removed (330') to reduce a weight of
the entire suspension 200, which improves a sound pressure.
[0030] FIGS. 8 to 10 are views showing a micro speaker according to a second embodiment
of the present invention. In the micro speaker according to the second embodiment
of the present invention, some parts of a top plate corresponding to solder land portions
are removed to prevent a suspension from colliding against the top surface of the
top plate and thus getting damaged due to its excess vibration caused by high power
vibration.
1. A suspension for a high power micro speaker that includes an outer peripheral portion,
a central portion and a connection portion, is provided with a conductive pattern,
and is formed in a rectangular shape,
wherein land portions for use in soldering or welding lead-in wires of a voice coil
are formed on long connection portions disposed on long sides.
2. The suspension of claim 1, wherein protective film for protecting the conductive pattern
is attached to the outer peripheral portion, the central portion and the connection
portion, and some parts of the protective film attached to the long connection portions
disposed on the long sides are removed.
3. The suspension of claim 1, wherein protective film for protecting the conductive pattern
is attached to the outer peripheral portion, the central portion and the connection
portion, and the protective film on the long connection portions disposed on the long
sides is removed.
4. The suspension of claim 1, wherein protective film for protecting the conductive pattern
is attached to the outer peripheral portion, the central portion and the connection
portion, and some part of the protective film on the central portion is removed.
5. The suspension of claim 1, wherein protective film for protecting the conductive pattern
is attached to the outer peripheral portion, the central portion and the connection
portion, and some parts of the protective films on short connection portions disposed
on short sides are removed.
6. A high power micro speaker, comprising:
a conductive suspension as recited in any one of claims 1 to 5; and
a voice coil, lead-in wires of which corresponding in direction to land portions of
the suspension.
7. A high power micro speaker, comprising:
a conductive suspension as recited in any one of claims 1 to 5; and
a voice coil, lead-in wires of which being drawn out from opposite diagonal positions
and shaped in a right-angle direction.