JP2017069692A - Speaker diaphragm and speaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a speaker diaphragm with reduced vibration by a simple configuration, and a speaker.SOLUTION: A rib 11d is formed on a body 11c of a diaphragm 11 along a radial direction R heading from an inner peripheral side edge portion 11b to an outer peripheral side edge portion 11a and the inner peripheral portion of the body 11c is formed as a thick portion 11e having a length L along the radial direction R having a thickness greater than that of the outer peripheral portion.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a speaker diaphragm that vibrates air and emits sound waves, and a speaker including the diaphragm.

  For example, the diaphragm described in Patent Document 1 includes a plurality of types of long-thickness portions and short-thickness-thickness portions having different lengths as thickness portions that gradually decrease in thickness from the inner peripheral side to the outer peripheral side. A thick part is formed. With these thick portions having different lengths, the divided vibration is reduced to improve the frequency characteristics.

JP 2012-138887 A

  The diaphragm described in Patent Document 1 needs to form a plurality of types of thick portions having different lengths, and the overall shape of the thick portions is complicated. Therefore, it is difficult to manufacture the diaphragm. In addition, since the shape is complicated, there are various dimensions to be considered when designing the thick portion, which requires a lot of labor.

  The present invention has been made in order to solve the above-described problems, and a diaphragm in which divided vibration is reduced by a configuration having a simpler shape than the conventional configuration for reducing divided vibration as described above. The purpose is to obtain.

  The speaker diaphragm according to the present invention includes a main body extending from the inner peripheral edge to the outer peripheral edge having a larger diameter than the inner peripheral edge, and the main body from the inner peripheral edge. Ribs formed along the radial direction toward the outer peripheral edge, and the inner peripheral portion of the main body portion is thicker than the outer peripheral portion and has a uniform radial length. It is characterized by being.

  According to the present invention, the divided vibration of the diaphragm can be reduced by the simple configuration of the thick portion having a uniform length in the radial direction in addition to the ribs formed along the radial direction.

It is sectional drawing of the speaker which concerns on Embodiment 1 of this invention. It is the top view and sectional drawing of a diaphragm which concern on Embodiment 1 of this invention. It is sectional drawing which shows a mode that the division | segmentation vibration has generate | occur | produced with the diaphragm. It is sectional drawing of the speaker which concerns on Embodiment 2 of this invention. It is the top view and sectional drawing of an annular member.

Embodiment 1 FIG.
FIG. 1 shows a cross-sectional view of a speaker 1 according to Embodiment 1 of the present invention.
The speaker 1 has a substantially cone-shaped diaphragm 11. The diaphragm 11 has an outer peripheral edge portion 11a positioned on the front side, which is above the paper surface, fixed to one end of the annular edge 12 in a plan view, and is positioned on the rear side and having a smaller diameter than the outer peripheral edge portion 11a. The inner peripheral edge 11 b is fixed to the voice coil 13. The other end of the edge 12 is fixed to a frame (not shown).

The voice coil 13 has a substantially cylindrical shape and is provided on the rear side of the diaphragm 11 and is connected to a frame (not shown) via a damper 14. A dome-shaped cap 15 is provided on the front side of the voice coil 13. The cap 15 has a peripheral edge portion 15 a fixed to the diaphragm 11 so as to cover the central portion of the diaphragm 11 and the voice coil 13. Since the diameter of the peripheral edge portion 15a of the cap 15 is formed larger than the diameter of the inner peripheral edge portion 11b of the diaphragm 11, the cap 15 can prevent foreign matter from entering the inside of the speaker 1, so-called dust. Acts as a cap.
Further, the speaker 1 has a magnet (not shown) that generates a magnetic field for vibrating the voice coil 13.

Here, FIG. 2A shows a plan view of the diaphragm 11, and FIG. 2B shows a cross-sectional view of the diaphragm 11. The plan view of FIG. 2A shows the diaphragm 11 as viewed from the rear side, and shows the back surface of the diaphragm 11. 2B is a cross-sectional view of the diaphragm 11 taken along the line AA in FIG.
The diaphragm 11 has a substantially conical surface-shaped main body portion 11c extending from the inner peripheral side edge portion 11b to the outer peripheral side edge portion 11a, and the main body portion 11c includes the inner peripheral side edge portion 11b to the outer peripheral side edge. A rib 11d, which is a protrusion extending along the radial direction R toward the portion 11a, is integrally formed. Although the total number of ribs 11d shown in FIG. 2 is five, the number thereof may be any number.
Further, the inner peripheral portion of the main body portion 11c of the diaphragm 11 is an annular thick portion 11e having a uniform thickness with a thickness greater than that of the outer peripheral portion. The thick portion 11e has a uniform length L along the radial direction R, and the outer edge 11f of the thick portion 11e is circular.
The diaphragm 11 is a resin diaphragm manufactured by, for example, injection molding.

In the speaker 1 configured as described above, when an audio signal is input to the voice coil 13, the voice coil 13 vibrates along the axial direction X of the speaker 1 according to the audio signal. Since the diaphragm 11 is fixed to the voice coil 13, the diaphragm 11 also vibrates with the vibration of the voice coil 13. When the diaphragm 11 vibrates, the air around the diaphragm 11 vibrates and a sound wave is emitted.
The diaphragm 11 has high rigidity due to the ribs 11d. Thereby, while the propagation speed of a sound wave becomes high, the diaphragm 11 becomes difficult to bend, and division vibration is reduced. Further, since the thick portion 11e is formed, the strength of the diaphragm 11 is high, and the divided vibration is further reduced. By reducing the divided vibration, the peak or dip is reduced in the frequency characteristic related to the sound pressure, the frequency characteristic is flattened, and high-quality sound can be reproduced.

  Since the thick portion 11e increases the strength of the inner peripheral portion, it is effective in reducing the divided vibration at the frequency from the middle range to the high range, and effectively reduces the peak or dip at the frequency. Can be made. For example, when a music piece is played back, the listener feels harsh when a peak appears in the vicinity of 3 kHz. However, by appropriately designing the dimensions of the rib 11d and the thick portion 11e, the divided vibration in the vicinity of 3 kHz can be reduced significantly. Thus, it is possible to prevent such discomfort.

  As described above, according to the speaker 1 according to the first embodiment, the diaphragm 11 is provided with the rib 11d and the thick portion 11e, so that the divided vibration of the diaphragm 11 is reduced. As a result, the frequency characteristics are flattened, and high-quality sound can be reproduced. The rib 11d, which is a protrusion formed along the radial direction R, and the thick portion 11e having a uniform length along the radial direction R each have a simple configuration.

  In the above description, the case where the rib 11d and the thick portion 11e are configured to be convex on the back surface of the diaphragm 11 has been described as an example. However, one or both of the rib 11d and the thick portion 11e may be configured to be convex on the surface of the diaphragm 11. Moreover, you may comprise so that the thick part 11e may become convex on both the surface of the diaphragm 11, and a back surface.

Embodiment 2. FIG.
In Embodiment 1, the vibration is reduced by providing the diaphragm 11 with the rib 11d and the thick portion 11e. In the second embodiment, a mode capable of further reducing the divided vibration will be described.
FIG. 1 is used for the configuration of the speaker 1 according to the second embodiment of the present invention.

  FIG. 3 schematically shows the state of the diaphragm 11 when the divided vibration is generated in an enlarged cross-sectional view. The position of the diaphragm 11 when not vibrating is indicated by a dotted line in FIG. The divided vibrations shown in FIG. 3 are in opposite phases on the outer peripheral side and the inner peripheral side with respect to the part P, and the position of the part P can be said to be a vibration node. In this case, the diameter of the cap 15 is designed so that the peripheral edge portion 15a of the cap 15 is fixed to the diaphragm 11 at any position P. Thereby, the site | part P used as a node when the diaphragm 11 carries out a divided vibration is made into a fixed location with the cap 15, and the intensity | strength of the site | part P is raised. By doing in this way, the vibration which made the part P the node can be attenuated effectively, and the divided vibration of the diaphragm 11 is further reduced.

Increasing the strength of the part P is effective in reducing the divided vibration at the frequency from the middle to high frequencies, as in the first embodiment, and effectively reducing the peak or dip at the frequency. be able to. In addition, by appropriately designing the strength of reinforcement by the cap 15, it is possible to intensively reduce the peak or dip at a frequency at which a listener, for example, around 3 kHz, particularly feels an annoyance.
The cap 15 is fixed to the diaphragm 11 with an adhesive or the like.

  By using the cap 15 as the reinforcing material for the part P, it is possible to reduce the divided vibration without increasing the number of parts. However, if another member is newly prepared and used as the reinforcing material for the part P Good. For example, an annular member may be prepared and fixed to the front surface or the back surface of the diaphragm 11 at the position P. In short, it is only necessary that a circular member is fixed to a portion P that becomes a vibration node when the diaphragm 11 vibrates in a divided manner.

FIG. 4 is a cross-sectional view when a configuration in which a member is fixed to the portion P and reinforced is applied to the speaker 2 that is a double cone speaker. The speaker 2 further has a substantially cone-shaped second diaphragm 21 on the inner peripheral side of the diaphragm 11.
As for the 2nd diaphragm 21, the outer peripheral side edge part 21a located in the front side is a free end, and the inner peripheral side edge part 21b located in the back side is being fixed to the voice coil 13. As shown in FIG. The central portion 21c of the second diaphragm 21 is formed in a dome shape to prevent foreign matter from entering the speaker 2. That is, the second diaphragm 21 also has a function as a dust cap.

An annular member 22 is provided around the second diaphragm 21 with a gap from the second diaphragm 21, and the annular member 22 is a position of a portion P that serves as a vibration node when the diaphragm 11 vibrates in a divided manner. Thus, it is fixed to the diaphragm 11. FIG. 5A shows a plan view of the annular member 22, and FIG. 5B shows a cross-sectional view of the annular member 22. The cross-sectional view of FIG. 5B is obtained by cutting the annular member 22 along the line BB of FIG. The annular member 22 is formed in an annular shape having a hole 22a in the central portion.
With this annular member 22 serving as a reinforcing material for the portion P, even the double cone speaker 2 without the cap 15 can further reduce the divided vibration.

More preferably, the cap 15 and the annular member 22 are made of a material that attenuates vibration. For example, felt, rubber, glass fiber and the like. In particular, if the glass fiber is used, the influence on the vibration of the diaphragm 11 necessary for sound reproduction can be reduced, so that it is possible to suppress the decrease in sound pressure during reproduction while reducing the divided vibration.
The annular member 22 can also be created by hollowing out the central portion of the cap 15 into a circle.

Note that a double-cone speaker having the second diaphragm 21 that also functions as a dust cap generally does not have a member that reinforces the diaphragm 11 like an annular member 22 in the first place. Therefore, the rigidity of the diaphragm 11 can be increased by fixing the annular member 22 to the diaphragm 11 not only at the part P but also at a part between the inner peripheral edge 11b and the outer peripheral edge 11a. Therefore, when compared with a general double cone speaker, the divided vibration can be further reduced.
Further, although the case where the annular member 22 is fixed to the surface of the diaphragm 11 has been described as an example, the annular member 22 may be fixed to the back surface of the diaphragm 11.

  As described above, according to the loudspeakers 1 and 2 according to the second embodiment, the cap 15 or the annular member 22 is fixed to the portion P that becomes a vibration node when the diaphragm 11 vibrates. Thereby, the divided vibration can be further reduced as compared with the first embodiment.

  Further, the circular member fixed to the portion P is a cap 15 having a larger diameter than the inner peripheral edge 11 b of the diaphragm 11 and covering the central portion of the diaphragm 11 while being fixed to the diaphragm 11. did. By using the cap 15, it is possible to reduce the divided vibration without increasing the number of parts.

  In addition, the circular member and the annular member 22 fixed to the portion P are made of glass fiber. Therefore, it is possible to suppress a decrease in sound pressure during reproduction while reducing divided vibration.

  In the present invention, within the scope of the invention, any combination of the embodiments, or any modification of any component in each embodiment, or omission of any component in each embodiment is possible. .

  1, 2 Speaker, 11 Diaphragm, 11a Outer peripheral edge, 11b Inner peripheral edge, 11c Main body, 11d Rib, 11e Thick part, 11f Outer edge, 12 edge, 13 Voice coil, 14 Damper, 15 Cap, 15a peripheral edge part, 21 2nd diaphragm, 21a outer peripheral side edge part, 21b inner peripheral side edge part, 21c center part, 22 annular member, 22a hole.

Claims (8)

A main body extending from the inner peripheral edge to the outer peripheral edge having a larger diameter than the inner peripheral edge;
The main body includes a rib formed along a radial direction from the inner peripheral edge to the outer peripheral edge,
The speaker diaphragm, wherein an inner peripheral portion of the main body is thicker than an outer peripheral portion and has a uniform length in the radial direction.   A speaker comprising the diaphragm of the speaker according to claim 1.   The speaker according to claim 2, further comprising a circular member fixed to a portion that becomes a vibration node when the vibration plate performs divided vibration.   4. The speaker according to claim 3, wherein the circular member is a cap that is larger in diameter than an inner peripheral edge of the diaphragm and is fixed to the diaphragm and covers a central portion of the diaphragm. .   The speaker according to claim 3 or 4, wherein the circular member is made of glass fiber. A second diaphragm provided on the inner peripheral side of the diaphragm;
The speaker according to claim 2, further comprising: an annular member fixed to the diaphragm at a portion between the inner peripheral side edge and the outer peripheral side edge.   The speaker according to claim 6, wherein the annular member is fixed to a portion that becomes a node of vibration when the diaphragm vibrates.   The speaker according to claim 6 or 7, wherein the annular member is made of glass fiber.

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