close

Вход

Забыли?

вход по аккаунту

?

JPS58138198

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 JPS58138198
[0001]
The present invention relates to a speaker for driving a node of a vibration mode of a diaphragm,
and more particularly to a speaker having an improved position to support a diaphragm by an
edge. A conventional flat loudspeaker is shown in FIG. This speaker has a flat plate-like
diaphragm 1, an edge 2 adhered to the outer peripheral portion of the diaphragm 1, and a conelike shape in which an enlarged diameter portion end is joined to a node of the primary divided
vibration mode of the diaphragm 1. It is bonded to the drive cone 3 and the voice coil 4 which is
joined to the end of the reduced diameter portion of the drive cone 3 and drives the diaphragm 1
via -C via the drive cone 3 and the outer peripheral wall of the voice coil 4 The voice coil 4 is
supported by a damper 5, a frame 6 to which the damper 5 and the edge 2 are fixed, and a
magnetic circuit 7 for driving the voice coil 4. It is known that by driving the nodes of the
vibration mode of the diaphragm 1, the speaker having such a structure can expand the
reproduction frequency band as the speaker. That is, driving a node of the axisymmetric firstorder divided vibration mode cancels the first-order divided vibration mode and flattens the
sound pressure characteristic in the vicinity of the frequency f1. The sound pressure
characteristics of the second-order divided vibration frequency f, which occurs at the following
frequency, can also be made flat. By the way, the position of the node of the above-mentionednext division vibration mode is determined as follows. That is, according to the classical theory of
a flat circular diaphragm, the position of the node of the diaphragm having the boundary
condition of peripheral freedom is as follows: when the radius of the diaphragm is a and the
radius fr of the node, r in fl is about a It becomes 0.68 times (0.68 a in r). However, in the
conventional speaker, as described above, since the diaphragm 1 is supported by the edge 2 at its
outer peripheral portion, the boundary condition of the diaphragm 1 is not free at the periphery
and is in an elastic support state . For this reason, the resonant frequency and the vibration mode
of the diaphragm itself change under the influence of the edge 2 and fI slightly decreases, so r
11-05-2019
1
also becomes larger than 0.68 a (Mitsubishi Electric branch axis Hee, Sakai) Vot, 54, No. 12 See
1980). And there existed a problem that a resonant frequency will fall if r becomes large like this.
The present invention has been made in view of the above-described point, and an object of the
present invention is to provide a speaker in which the resonance frequency and the vibration
mode of the diaphragm itself are not affected by the edge. Hereinafter, embodiments of the
present invention will be described with reference to the drawings. A loudspeaker according to
the invention is shown in FIG. This speaker comprises a flat plate-like diaphragm 1, a coneshaped drive cone 3 whose enlarged diameter end is joined to a node of the primary divided
vibration mode of the diaphragm 1, and a diameter-reduced portion end of the cone 3 A voice
coil 4 for driving the diaphragm 1 through a driving cone 3, a damper 5 bonded to the outer
peripheral wall of the voice coil 4 to support the coil 4, and the damper 5 fixed And a magnetic
circuit 7 for driving the voice coil 4.
In the loudspeaker according to the present invention, the diaphragm 1 is supported by one end
of the edge 2 at the junction of the drive cone 3, that is, at the node of the primary divided
vibration mode. The other end of the edge 2 is fixed to the frame 6 along the back surface of the
diaphragm 1. When the diaphragm 1 is thus supported by the edge 2 via the above node, there is
no change in the inherent resonance frequency and vibration mode (eigenfunction) relating to
the first-order divided vibration of the diaphragm 1. If you go round it, the node r of the vibration
mode agrees with 0, 68 a according to the classical theory (refer to Journal of the Acoustical
Society of Japan (Heisuke, Suzuki, Shindou) 34: 8, 1978). Another embodiment of the present
invention is shown in FIG. In this embodiment, the voice coil 4 is formed in a cylindrical shape so
as to have the same diameter as the node of the primary divided vibration mode of the
diaphragm l, and the toe end of the voice coil 4 is directly attached to the position of the node of
the diaphragm 1 An example of bonding is shown. Although in the above two embodiments, an
example using a flat circular diaphragm is shown, the same effect can be obtained by using a
cone-shaped or dome-shaped diaphragm. Further, although an example of driving the node of the
primary divided vibration mode of the diaphragm is shown in the above embodiment, the
invention can be applied to a speaker for driving the node of the secondary vibration mode or
more of secondary, and similar effects can be obtained. Can. As apparent from the above
description, according to the present invention, in the speaker for driving the node of the
vibration mode of the diaphragm, since the node is supported by the edge, the resonance
frequency and the vibration mode unique to the diaphragm are edges. It is hardly affected, and
therefore, a speaker with excellent acoustic characteristics can be obtained.
[0002]
Brief description of the drawings
11-05-2019
2
[0003]
FIG. 1 is a sectional view of a conventional flat panel loudspeaker, FIG. 2 is a sectional view of a
flat panel loudspeaker according to the present invention, and FIG. 3 is a sectional view of a
loudspeaker according to another embodiment of the present invention.
DESCRIPTION OF SYMBOLS 1 ... Diaphragm, 2 ... Edge, 3 ... Cone for drive, 4 ... Heuss coil, 5 ...
Damper, 6 ... Frame, 7 ... Magnetic circuit. In the drawings, the same reference numerals denote
the same or corresponding parts. Agent Akebono Shino-1) Fig. 2 Fig. 3 Fig. 3 Procedure
amendment (spontaneous) Patent office secretary 2, name of invention speaker 3, relationship
with case making correction Patent applicant Residence Chiyoda-ku, Tokyo Marunouchi Two J
Doo 12th 3. >, 3 persons (601) Mitsubishi Electric Corporation representative Yuhito Katayu 8
part, agent residence Tokyo, Tokyo Nanashiro IJi Ward Marunouchi 12 No. 3 5, Detailed
explanation of the invention of the subject specification of the amendment Column. 6. Contents
of correction (1) In the specification, page 2, line 18, "The sound pressure characteristics of the
divided vibration frequency f2 can be made flat" is corrected as "the sound pressure
characteristics up to near the divided vibration frequency f2 can be made flat". (2) On page 3,
line 11, "Because it falls" is corrected as "Degraded". (3) On the same page, page 13 to line 14
"and when it gets larger" is corrected as "as described above, r becomes larger in the
conventional speaker". that's all
11-05-2019
3
Документ
Категория
Без категории
Просмотров
0
Размер файла
11 Кб
Теги
jps58138198
1/--страниц
Пожаловаться на содержимое документа