close

Вход

Забыли?

вход по аккаунту

?

JPH09154193

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 JPH09154193
[0001]
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a
magnetic shield type speaker used for various AV equipment and the like, and more particularly
to a magnetic shield type speaker having a repulsion type magnetic circuit.
[0002]
2. Description of the Related Art As a conventional magnetic shield type speaker, a magnetic
shield type speaker having a repulsion type magnetic circuit as shown in FIG. 2 is known. In the
figure, 1 is a center pole, 1a is a plate portion of the center pole, 2 is an upper plate, 3 is a main
magnet disposed between the plate portion 1a and the upper plate 2, and 4 is the same pole as
the main magnet 3 Repulsion magnet arranged to face each other, 15 is a frame installed on the
upper plate 2, 16 is a repulsion type magnetic element having the center pole, the upper plate 2,
the main magnet 3 and the repulsion magnet 4 as components. It is an outer yoke that forms the
outer periphery and the bottom of the circuit.
[0003]
The magnetic flux from the main magnet 3 passes through → top plate 2 → center pole 1 →
plate portion 1 a and returns to the main magnet 3. The magnetic flux from the repulsion magnet
4 returns to the repulsion magnet 4 through → outer yoke 16 → upper plate 2 → center pole 1
13-05-2019
1
→ plate portion 1 a. Although not shown, a voice coil is installed in the magnetic gap formed by
the upper plate 2 and the center pole 1, and the diaphragm of the connected speaker is vibrated
by supplying an audio current to the voice coil.
[0004]
However, the outer yoke 16 is used in the magnetically shielded speaker having the repulsion
type magnetic circuit in the above-mentioned conventional example. The outer yoke 16 requires
a large number of steps in order to form it into a required shape by drawing, and including the
number of steps for bonding the repulsion magnet 4 and the outer yoke 16 to the speaker body
is extremely expensive.
[0005]
Furthermore, in the figure, assuming that the diameter of the outer yoke 16 is D and the plate
thickness is t, the cross-sectional area of the outer peripheral portion is πDt, and the crosssectional area of the bottom varies depending on the distance from the center and is π (0 to D) t.
. Essentially, the cross-sectional area of the outer yoke 16 is desirably constant, and the outer
peripheral portion may be thinner than the bottom. However, the thickness of the outer yoke 16
is constant because the plate material is narrowed, and the cross-sectional area of the outer
peripheral portion becomes large, which is inefficient. Another problem is that the magnetic flux
of the main magnet 3 is transmitted through the upper plate 2 to the frame 15 to lead to the
generation of a leakage magnetic flux.
[0006]
The present invention has been made in view of these points, and provides a magnetically
shielded speaker having a repulsion magnetic circuit in which occurrence of magnetic flux
leakage from the frame is eliminated by eliminating the outer yoke having many problems. The
purpose is to
[0007]
[Means for Solving the Problems] In order to solve the above problems, in the magnetically
shielded speaker of the present invention, the outer yoke used conventionally is eliminated, and
13-05-2019
2
one end of the frame is extended to the repulsion magnet side to form a center pole, An outer
peripheral portion of a repulsion type magnetic circuit having an upper plate, a main magnet,
and a repulsion magnet as components is formed.
Further, the back plate of the iron plate is placed on the back of the repulsion magnet and joined
to the frame to form the bottom of the repulsion type magnetic circuit. Therefore, efficiently
designing the ratio between the thickness of the frame covering the entire outer peripheral side
constituting the repulsion type magnetic circuit and the thickness of the iron plate covering the
entire lower side constituting the repulsion type magnetic circuit it can. In addition, it is possible
to reduce the manufacturing cost of the magnetically shielded speaker provided with the
repulsion type magnetic circuit having an excellent function by reducing the number of
processes.
[0008]
BEST MODE FOR CARRYING OUT THE INVENTION In the magnetically shielded speaker of the
present invention, the main magnet is disposed between the upper plate and the plate portion of
the center pole, and the repulsion magnet is disposed on the back of the plate portion of the
center pole. A magnetically shielded speaker having a repulsion type magnetic circuit, wherein
the outer peripheral portion of the repulsion type magnetic circuit is formed by extending one
end of the frame linearly from the outer peripheral portion of the upper plate to the outer
peripheral side of the repulsion magnet And the bottom of the repulsion type magnetic circuit is
formed by covering a back plate of an iron plate.
[0009]
An embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 is a half cross-sectional view of a repulsion type magnetic circuit in a magnetic speaker of
an embodiment of the present invention. In addition, what attached | subjected the code | symbol
same as FIG. 1 has shown the same element, respectively, and abbreviate | omits description. In
the figure, 1 is a center pole, 1a is a plate portion of the center pole, 2 is an upper plate, 3 is a
main magnet, 4 is a repulsion magnet, 5 is a frame, and 6 is a back plate. The frame 5 and the
back plate 6 form the outer periphery and the bottom of the repulsion type magnetic circuit.
[0010]
13-05-2019
3
The magnetic flux from the main magnet 3 passes through → top plate 2 → center pole 1 →
plate portion 1 a and returns to the main magnet 3. The magnetic flux from the repulsion magnet
4 returns to the repulsion magnet 4 through → back plate 6 → frame 1 → upper plate 2 →
center pole 1 → plate portion 1 a.
[0011]
As in the case of the frame 5 shown in the embodiment of the present invention, one end of the
frame 15 bonded to the upper plate 2 shown in the conventional example is extended to the
outer peripheral side of the repulsion magnet 4 and used together with the back plate 6. Thus,
the conventional outer yoke 16 can be eliminated. Since the outer yoke 16 is expensive both in
material cost and processing cost, the cost can be significantly reduced by eliminating it. Further,
the ratio of the thickness of the frame forming the outer peripheral portion of the repulsion type
magnetic circuit to the thickness of the iron plate forming the bottom portion of the repulsion
type magnetic circuit can be efficiently designed. Although the outer periphery is the frame 5
and is usually thinner than the back plate 6, since the cross-sectional area is almost the same,
equivalent performance can be obtained, which is a rational design.
[0012]
As described above, in the magnetically shielded speaker according to the present invention, the
outer peripheral portion of the repulsion type magnetic circuit is linearly extended from the
outer peripheral portion of the upper plate to the outer peripheral side of the repulsion magnet.
Since the bottom portion of the repulsion type magnetic circuit is formed by covering the back
plate of the iron plate, the shape of the frame of the portion forming the outer peripheral portion
of the repulsion type magnetic circuit is simple and easy to process, In combination with the use
of the back plate, the material cost and the processing cost are both lower than in the outer yoke,
resulting in cost reduction. Moreover, although an outer peripheral part becomes a frame and
becomes usually thinner than a back plate, in the cross-sectional area, since it is almost the same,
equivalent performance can be obtained and it is a rational design.
[0013]
Brief description of the drawings
13-05-2019
4
[0014]
1 is a half cross-sectional view of a repulsion type magnetic circuit in a magnetic shield type
speaker according to an embodiment of the present invention.
[0015]
2 is a half sectional view of the repulsion type magnetic circuit in the conventional magnetic
shield type speaker.
[0016]
Explanation of sign
[0017]
Reference Signs List 1 center pole 1a center pole plate 2 upper plate 3 main magnet 4 repulsion
magnet 5, 15 frame 6 back plate 16 outer yoke
13-05-2019
5
Документ
Категория
Без категории
Просмотров
0
Размер файла
12 Кб
Теги
jph09154193
1/--страниц
Пожаловаться на содержимое документа