JP2023110691A - speaker - Google Patents

Abstract

To provide a speaker capable of increasing sound pressure.SOLUTION: A speaker 1 comprises: an outer case 2 as a base; a magnetic circuit part 3 attached to the base; a vibration part 41 that covers the magnetic circuit part; and a voice coil 5 connected with the vibration part and located between the vibration part and the magnetic circuit part. The magnetic circuit part has: a first yoke 31 that has a pillar part 312, and a first flange part 311 provided at an end part opposed to the vibration part, of the pillar part; a second yoke 32 provided around an end part at the vibration part side of the pillar part so that a gap for inserting the voice coil is generated between the first yoke and itself; a first magnet 33 sandwiched between the first flange part and the second yoke; and a second magnet 34 arranged on at least one of the pillar part and the second yoke at an opposite side to the first flange part so as to increase a magnetic flux toward the voice coil.SELECTED DRAWING: Figure 1

Description

The present invention relates to loudspeakers, for example underwater loudspeakers.

A conventional speaker is disclosed in Patent Document 1 (Japanese Patent No. 3057039). This speaker includes a diaphragm, an aluminum tube with one end attached to the diaphragm, a coil wound around the outer peripheral surface of the other end of the aluminum tube, and a magnetic circuit.

The magnetic circuit section has a first yoke and a second yoke closer to the diaphragm than the first yoke. A magnet is arranged between the first yoke and the second yoke to generate a magnetic flux toward the coil.

Japanese Patent No. 3057039

In the speaker of Patent Document 1, when an audio signal is supplied to the coil, the coil vibrates in the axial direction. At this time, the sound pressure is determined according to the excitation force of the coil, but there is room for an increase in this sound pressure.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a loudspeaker capable of increasing sound pressure.

A speaker according to one aspect of the present invention includes
a base;
a magnetic circuit unit attached to the base;
a vibrating portion covering the magnetic circuit portion;
a voice coil connected to the vibrating portion and positioned between the vibrating portion and the magnetic circuit;
The magnetic circuit unit is
a first yoke having a column portion and a flange portion provided at an end portion of the column portion opposite to the vibrating portion;
a second yoke provided around an end portion of the column portion on the vibrating portion side such that a gap for inserting the voice coil is formed between the column portion and the first yoke;
a first magnet sandwiched between the flange portion and the second yoke;
A second magnet is arranged on the side opposite to the flange portion with respect to at least one of the column portion and the second yoke so as to increase the magnetic flux toward the voice coil.

According to the aspect, the magnetic flux formed by the first magnet and the magnetic flux formed by the second magnet are added. Therefore, the magnetic flux that contributes to the axial vibration of the voice coil increases compared to the case where the magnetic circuit section does not have the second magnet. Therefore, it is possible to increase the sound pressure by increasing the vibration force of the voice coil.

In one aspect of the speaker,
The second magnet is arranged radially outward of the voice coil.

According to the aspect, since the second magnet is arranged radially outside the voice coil, it is possible to suppress an increase in the size of the speaker in the axial direction.

Further, by arranging the second magnet radially outside the voice coil, the radial size of the second magnet can be made larger than the outer diameter of the voice coil. Therefore, compared to the case where the second magnet is arranged radially inside the voice coil, the magnetic flux contributing to the axial vibration of the voice coil can be increased.

In one aspect of the speaker,
The second magnet overlaps the first magnet in the axial direction of the voice coil.

According to the above aspect, the excitation force of the voice coil can be effectively increased compared to the case where the second magnet is not overlapped with the first magnet in the axial direction of the voice coil.

In one aspect of the speaker,
The second magnet is arranged radially inside the voice coil.

According to the aspect, since the second magnet is arranged radially inside the voice coil, it is possible to suppress an increase in the size of the speaker in the axial direction.

In addition, by arranging the second magnet radially inside the voice coil, it is possible to prevent the empty space radially outside the voice coil from becoming smaller. Therefore, it is possible to increase the degree of freedom in designing the radially outer side of the voice coil.

In one aspect of the speaker,
The second magnet has a third magnet arranged radially outside the voice coil and a fourth magnet arranged radially inside the voice coil.

According to the aspect, since the third magnet is arranged radially outside the voice coil and the fourth magnet is arranged radially inside the voice coil, only one of the third magnet and the fourth magnet is arranged. Magnetic flux that contributes to the axial vibration of the voice coil can be increased compared to the case where

In one aspect of the speaker,
The vibrating portion is a cylindrical body that accommodates the base, the voice coil, and the magnetic circuit portion,
The base has a first end located on one side in the radial direction of the cylinder and a second end located on the other side in the radial direction of the cylinder,
The first end is fixed to the inner peripheral surface on one side in the radial direction of the cylindrical body,
The second end portion is fixed to the inner peripheral surface on the other side in the radial direction of the tubular body.

According to the above aspect, by fixing the first end portion and the second end portion, the vibrating portion can be supported by the base from the inside of the vibrating portion, thereby reinforcing the vibrating portion.

In the speaker of the present invention, the second magnet is arranged on the opposite side of the second yoke from the flange portion so that the magnetic flux directed to the voice coil increases, so the sound pressure can be increased.

1 is a vertical cross-sectional view of a speaker according to a first embodiment of the present disclosure; FIG. FIG. 2 is a partially enlarged view schematically showing a magnetic circuit portion and a voice coil of the speaker shown in FIG. 1 and a magnetic flux generated in the magnetic circuit portion and the voice coil, omitting other portions; FIG. 5 is a vertical cross-sectional view of a speaker according to a second embodiment of the present disclosure; FIG. 4 is a partially enlarged view schematically showing the magnetic circuit portion and voice coil of the speaker shown in FIG. 3 and the magnetic flux generated in the magnetic circuit portion and voice coil, and omitting other portions; FIG. 11 is a vertical cross-sectional view of a speaker according to a first modified example of the second embodiment of the present disclosure; FIG. 11 is a vertical cross-sectional view of a speaker according to a second modified example of the second embodiment of the present disclosure; FIG. 10 is a vertical cross-sectional view of a speaker according to a third embodiment of the present disclosure; FIG. 8 is a partially enlarged view schematically showing the magnetic circuit portion and voice coil of the speaker shown in FIG. 7 and the magnetic flux generated in the magnetic circuit portion and voice coil, and omitting other portions; FIG. 11 is a vertical cross-sectional view of a speaker according to a first modified example of the third embodiment of the present disclosure; FIG. 10 is a vertical cross-sectional view of a speaker according to a second modified example of the third embodiment of the present disclosure;

Hereinafter, embodiments and modifications thereof according to the present disclosure will be described in detail based on the drawings.

(First embodiment)
FIG. 1 is a vertical cross-sectional view of a speaker 1 according to the first embodiment of the present disclosure.

(Configuration of speaker 1)
The speaker 1 includes an exterior case 2 as an example of a base, a magnetic circuit section 3 , a lid section 4 and a voice coil 5 . This speaker 1 is, for example, an underwater speaker that can be used at a depth of 10 m.

The exterior case 2 is formed in the shape of an open container. The exterior case 2 has a peripheral wall portion 21 and a bottom portion 22 . The peripheral wall portion 21 is formed integrally with the bottom portion 22 and has one end connected to the peripheral portion of the bottom portion 22 . The inner peripheral surface of the peripheral wall portion 21 on the other end side is provided with a plurality of recesses 21a capable of accommodating the heads of screws described later. The exterior case 2 is made of a material that has heat resistance and does not easily deteriorate over time. Although the exterior case 2 is made of stainless steel in this embodiment, it may be made of, for example, copper, aluminum, or hard heat-resistant resin (for example, heat-resistant plastic).

The magnetic circuit unit 3 is attached to the exterior case 2 via a first elastic member 61 which will be described later, and is mostly housed in the exterior case 2 . The magnetic circuit section 3 has a first yoke 31 , a second yoke 32 , a first magnet 33 and a second magnet 34 . More specifically, the magnetic circuit section 3 is covered with a diaphragm 41 of the lid section 4, which will be described later. A voice coil 5 , which will be described later, is positioned between the magnetic circuit portion 3 and the lid portion 4 . An electric signal line 8 outside the speaker 1 is electrically connected to the magnetic circuit portion 3 .

The first yoke 31 has a first flange portion 311 as an example of a flange portion, a column portion 312 and a second flange portion 313 . This first yoke 31 is made of, for example, a ferromagnetic material or a paramagnetic material.

The columnar portion 312 is formed in a cylindrical shape and has a central axis parallel to the central axis of the voice coil 5 . The column portion 312 has a first end portion 312a on the side of the lid portion 4 opposite to the diaphragm 41 side, that is, on the bottom portion 22 side of the outer case 2, and a second end portion on the diaphragm 41 side of the lid portion 4. It has a portion 312b.

The first flange portion 311 is formed in an annular shape. The first flange portion 311 is provided at a first end portion 312 a of the column portion 312 and has an outer diameter larger than the outer diameter of the column portion 312 . A first surface 311 a of the first flange portion 311 faces the bottom portion 22 of the exterior case 2 . On the other hand, a second surface 311 b of the first flange portion 311 opposite to the first surface 311 a faces the voice coil 5 .

The outer diameter of the second flange portion 313 is smaller than the outer diameter of the first flange portion 311 but has the same shape as the first flange portion 311 . That is, the second flange portion 313 is formed in an annular shape. The second flange portion 313 is provided at the second end portion 312 b of the column portion 312 and has an outer diameter larger than the outer diameter of the column portion 312 . The second flange portion 313 is attached to the diaphragm of the lid portion 4 so that the first surface 313a faces the diaphragm 41 side of the lid portion 4 and the second surface 313b faces the bottom portion 22 side of the exterior case 2 . 41 and the bottom portion 22 of the exterior case 2 .

Further, the first yoke 31 is provided with a through hole 31h extending from one end surface of the first yoke 31 in the axial direction to the other end surface of the first yoke 31 in the axial direction. The through hole 31 h extends along the central axis direction of the column portion 312 and is defined by the inner peripheral surface of the column portion 312 .

The second yoke 32 is provided around the second flange portion 313 so that a gap for inserting the voice coil 5 is created between the second yoke 32 and the first yoke 31 . In other words, the second yoke 32 is formed in an annular shape so as to surround the second flange portion 313 and has an inner diameter larger than the outer diameter of the second flange portion 313 . The outer diameter of the second yoke 32 is set to be larger than the outer diameter of the first flange portion 311 of the first yoke 31 . The first surface 32 a of the second yoke 32 is arranged on the diaphragm 41 side of the lid portion 4 . On the other hand, the second surface 32b of the second yoke 32 opposite to the first surface 32a is arranged on the bottom portion 22 side of the exterior case 2 . Like the first yoke 31, the second yoke 32 is also made of, for example, a ferromagnetic material or a paramagnetic material. The second yoke 32 is attached to the peripheral wall portion 21 of the exterior case 2 via the first elastic member 61 .

The first magnet 33 is sandwiched between the first flange portion 311 and the second yoke 32 . More specifically, the first magnet 33 is formed in an annular shape. The inner diameter of the first magnet 33 is set to be larger than the inner diameter of the second yoke 32 . On the other hand, the outer diameter of the first magnet 33 is set to be approximately the same as the outer diameter of the first flange portion 311 of the first yoke 31 . The magnetic pole of the first magnet 33 has an N pole on the first flange portion 311 side over the entire circumference, and an S pole on the second yoke 32 side over the entire circumference. The N pole of the first magnet 33 is fixed to the second surface 311 b of the first flange portion 311 . On the other hand, the south pole of the first magnet 33 is fixed to the second surface 32b of the second yoke 32. As shown in FIG.

The second magnet 34 is arranged on the side opposite to the first flange portion 311 with respect to the second yoke 32 and attached to the second yoke 32 . More specifically, the second magnet 34 is formed in an annular shape, and the inner peripheral surface faces a part of the voice coil 5 with a gap therebetween. The second magnet 34 overlaps the first magnet 33 in the axial direction of the voice coil 5 . The magnetic pole of the second magnet 34 has an S pole on the second yoke 32 side over the entire circumference, and an N pole on the diaphragm 41 side of the lid 4 over the entire circumference. The south pole of the second magnet 34 is fixed to the first surface 32 a of the second yoke 32 . On the other hand, the north pole of the second magnet 34 faces the space inside the lid portion 4 .

The magnetic circuit portion 3 having such a configuration is attached to the peripheral wall portion 21 of the exterior case 2 via the first elastic member 61 .

The lid portion 4 is attached to the exterior case 2 so as to block the opening of the exterior case 2 and forms a sealed space with the exterior case 2 . More specifically, the lid portion 4 has a diaphragm 41 as an example of a vibrating portion and a holding frame 42 that holds the diaphragm 41 .

The diaphragm 41 is shaped like an elastically deformable dish. In this embodiment, the diaphragm 41 is made of stainless steel, but is made of steel, titanium, aluminum, tile material, wood, or heat-resistant resin (for example, a mixed resin in which carbon is mixed with resin). may be formed. Alternatively, diaphragm 41 may be made of an elastic member. Diaphragm 41 has an arbitrary thickness so that speaker 1 can generate a predetermined sound pressure. A connecting member 451 , which will be described later, is connected to the central portion of the diaphragm 41 .

The holding frame 42 is formed in a cylindrical shape and provided around the diaphragm 41 . The holding frame 42 is attached to the peripheral wall portion 21 so that there is no gap between one end portion of the holding frame 42 and the other end portion of the peripheral wall portion 21 . The peripheral edge of the diaphragm 41 is connected to the inner peripheral surface of the other end of the holding frame 42 so that no gap is formed between the inner peripheral surface of the other end of the holding frame 42 and the peripheral edge of the diaphragm 41 . It is

The connection member 451 is formed in the shape of a lidded cylinder. A groove portion 451 a is provided in the outer peripheral edge portion of the connection member 451 . The connection member 451 is attached by screwing to the central portion of the surface of the diaphragm 41 facing the magnetic circuit portion 3 . In this embodiment, contact such as that between the diaphragm 41 and the connection member 451 is called point contact.

Voice coil 5 is located between diaphragm 41 and magnetic circuit section 3 . More specifically, voice coil 5 is connected to diaphragm 41 via connecting member 451 . The voice coil 5 has a bobbin portion 51 and a coil portion 52 .

The bobbin portion 51 is formed in a tubular shape. The bobbin portion 51 is made of paper or aluminum, for example. One axial end of the bobbin portion 51 is fixed by being fitted into the groove portion 451 a of the connecting member 451 . The other axial end of the bobbin portion 51 is located in the gap between the second flange portion 313 of the first yoke 31 and the second yoke 32 .

The coil portion 52 is spirally wound around the outer peripheral surface of the bobbin portion 51 on the other end side. The coil portion 52 is energized according to an electric signal input from the outside of the speaker 1 through the electric signal line 8 . The coil portion 52 is also located in the gap between the second flange portion 313 of the first yoke 31 and the second yoke 32 .

The speaker 1 also includes a first elastic member 61 , a second elastic member 62 and a compression spring 71 .

The first elastic member 61 holds the second yoke 32 . The first elastic member 61 has an annular body portion 611 and a plurality of arm portions 612 extending from the outer peripheral edge portion of the body portion 611 toward the bottom portion 22 . The body portion 611 is attached to the second yoke 32 . The plurality of arm portions 612 are attached to the peripheral wall portion 21 of the exterior case 2, respectively. More specifically, screws are attached to the distal end sides of the plurality of arm portions 612 of the first elastic member 61 . The heads of these screws are accommodated in a plurality of recesses 21a of the peripheral wall portion 21, respectively. The head of each screw is fixed to each recess 21a with an adhesive. In this embodiment, the first elastic member 61 is made of phosphor bronze, but may be made of, for example, stainless steel, steel, or heat-resistant resin (for example, mixed resin in which carbon is mixed with resin). can be

The second elastic member 62 is formed integrally with the connecting member 451 . More specifically, one end of the second elastic member 62 on the connecting member 451 side is connected to the outer peripheral edge of the connecting member 451 . The other end of the second elastic member 62 on the holding frame 42 side is connected to the first surface 32 a of the second yoke 32 via a plurality of spacers 63 . That is, the second elastic member 62 is indirectly connected to the first elastic member 61 . In the present embodiment, the second elastic member 62 is made of phosphor bronze, but may be made of, for example, stainless steel, steel, or heat-resistant resin (for example, mixed resin in which carbon is mixed with resin). may

The plurality of spacers 63 are arranged at predetermined intervals in the circumferential direction of the second yoke 32 . More specifically, the spacers 63 are connected to the first surface 32a of the second yoke 32, respectively.

The compression spring 71 is sandwiched between the connection member 451 and the first yoke 31 so that the central axis of the compression spring 71 is parallel to the central axis of the voice coil 5 . More specifically, the compression spring 71 is sandwiched between the connecting member 451 and the column portion 312 . The compression spring 71 is fixed to each of the connection member 451 and the column portion 312 with an adhesive. As a result, for example, when the speaker 1 receives water pressure from the outside and the diaphragm 41 is pushed into the speaker 1, a restoring force acting along the axial direction of the voice coil 5 is generated in the compression spring 71. , the compression spring 71 urges the magnetic circuit portion 3 toward the bottom portion 22 of the exterior case 2 .

(Operation of speaker 1)
In this embodiment, the first magnet 33 and the second magnet 34 form a first magnetic flux 331 and a second magnetic flux 341, respectively, which will be described later. When an electric signal is input from the outside of the speaker 1 through the electric signal line 8 , an electric signal corresponding to the processing result of a processing circuit (not shown) is supplied to the coil portion 52 of the voice coil 5 . At this time, since the coil portion 52 of the voice coil 5 is arranged in the first magnetic flux 331 and the second magnetic flux 341 , a Lorentz force proportional to the magnetic flux density acts on the voice coil 5 . This Lorentz force is an excitation force that vibrates the voice coil 5 in the axial direction, vibrating the voice coil 5 and the diaphragm 41 of the lid portion 4 connected to the voice coil 5 via the connection member 451, produce sound pressure. For example, when sound pressure is generated in a low-frequency sound range of 10 Hz to 400 Hz by generating low-frequency sound vibration, the mass of the magnetic circuit unit 3 is appropriately set in advance so that the voice coil 5 and the magnetic circuit unit 3 Resonate. Further, for example, when the voice coil 5 and the magnetic circuit section 3 resonate, the vibration of the magnetic circuit section 3 in the axial direction of the voice coil 5 increases, causing the air inside the speaker 1 to flow.

FIG. 2 is a partial enlarged view schematically showing the magnetic flux generated in the magnetic circuit section 3 of the speaker 1 shown in FIG.

When the first magnets 33 and the second magnets 34 are arranged as shown in FIGS. 1 and 2, the first magnetic flux 331 formed by the first magnets 33 and the second magnets 34, as shown in FIG. The formed second magnetic flux 341 is added. Therefore, the magnetic flux that contributes to the axial vibration of the voice coil increases compared to the case where the magnetic circuit section 3 does not have the second magnet 34 .

Therefore, the speaker 1 of the present embodiment can increase the sound pressure by increasing the excitation force of the voice coil by, for example, 20% compared to the case where the magnetic circuit section 3 does not have the second magnet 34 .

In addition, since the second magnet 34 is arranged radially outside the voice coil 5, it is possible to suppress an increase in the size of the speaker 1 in the axial direction.

Further, by arranging the second magnet 34 radially outside the voice coil 5 , the radial size of the second magnet 34 can be made larger than the outer diameter of the voice coil 5 . Therefore, compared to the case where the second magnet is arranged radially inside the voice coil 5, the magnetic flux contributing to the axial vibration of the voice coil 5 can be increased.

In addition, since the second magnet 34 overlaps the first magnet 33 in the axial direction of the voice coil 5, the excitation force that vibrates the voice coil 5 in the axial direction can be effectively increased.

Also, the second magnet 34 can be easily replaced without being disturbed by the voice coil 5 .

Further, when the speaker 1 receives water pressure from the outside, the diaphragm 41 is dented, and the connecting member 451 and the voice coil 5 move toward the exterior case 2 side. At this time, since the compression spring 71 is arranged between the first yoke 31 and the connecting member 451, when the water pressure decreases, the connecting member 451 and the voice coil 5 are urged by the urging force of the compression spring 71 to a predetermined degree. can be returned to position.

Further, when the connection member 451 and the voice coil 5 move toward the exterior case 2 , the compression spring 71 urges the magnetic circuit section 3 toward the bottom portion 22 of the exterior case 2 . The relative positional relationship with the voice coil 5 can be easily maintained, and a decrease in the Lorentz force that the voice coil 5 receives can be suppressed. Therefore, a decrease in the sound pressure emitted by the speaker 1 can be suppressed.

Further, by adjusting the thickness or material of the diaphragm 41 , it is possible to generate a predetermined sound pressure from the speaker 1 .

Also, since the voice coil 5 is connected to the magnetic circuit section 3 via the second elastic member 62 and the like, the natural frequency of the voice coil 5 is lowered. Therefore, among the sound pressures generated from the speaker 1, the sound pressure in the low range can be increased.

Further, the resonance of the voice coil 5 and the magnetic circuit section 3 can promote the flow of air inside the speaker 1 . As a result, it is possible to prevent heat from accumulating in the vicinity of the voice coil 5 .

(Second embodiment)
In the speaker 201 according to the second embodiment of the present disclosure, the second magnet 234 is arranged radially inside the voice coil 5, and the second elastic member 262 is formed separately from the connection member 451. It differs from the first embodiment. Moreover, it differs from the first embodiment in that the compression spring 71 is omitted. In addition, in the second embodiment, the same reference numerals are given to the same parts as in the first embodiment, the description thereof is omitted, and the points different from the first embodiment will be described.

FIG. 3 is a longitudinal sectional view of speaker 201 according to the second embodiment of the present disclosure.

The second magnet 234 is arranged radially inside the voice coil 5 . More specifically, the second magnet 234 is arranged radially inside the voice coil 5 on the side opposite to the first flange portion 311 with respect to the column portion 312 and on the second end portion 312b side of the column portion 312. and the first surface 313 a of the second flange portion 313 . The outer peripheral surface of the second magnet 234 faces a portion of the voice coil 5 with a gap therebetween. The magnetic pole of the second magnet 234 has an N pole on the side of the column 312 or the second flange 313 over the entire circumference, and an S pole on the side of the diaphragm 41 of the lid 4 over the entire circumference. The N pole of the second magnet 234 is in contact with the end surface of the column portion 312 on the second end portion 312 b side and the first surface 313 a of the second flange portion 313 . On the other hand, the south pole of the second magnet 234 faces the space inside the lid portion 4 .

The second elastic member 262 is formed separately from the connecting member 451 and connected to the connecting member 451 and the plurality of spacers 63 . The second elastic member 262 has an annular body portion 2621 fixed to the connecting member 451 and a plurality of arm portions 2622 extending from the outer peripheral edge of the body portion 2621 toward the spacer 63 . Each of the plurality of arm portions 2622 is connected to the first surface 32 a of the second yoke 32 via each spacer 63 at the ends opposite to the body portion 2621 .

FIG. 4 is a partial enlarged view schematically showing the magnetic flux generated in the magnetic circuit section 203 of the speaker 201 shown in FIG.

When the first magnets 33 and the second magnets 234 are arranged as shown in FIGS. 3 and 4, the first magnetic flux 331 formed by the first magnets 33 and the second magnets 234, as shown in FIG. The formed second magnetic flux 2341 is added. Therefore, the magnetic flux that contributes to the axial vibration of the voice coil increases compared to the case where the magnetic circuit section 3 does not have the second magnet 234 .

(First modification)
A speaker 1201 according to a first modification of the second embodiment of the present disclosure has a first exterior case 1202 configured with a peripheral wall portion 21 and a bottom portion 1222, and a second exterior so as to cover the first exterior case 1202. It differs from the first embodiment or the second embodiment in that a case 1223 is provided and a pad 1243 is provided on the lid portion 1204 . In addition, in this modified example, the same reference numerals are given to the same parts as those of the first embodiment or the second embodiment, and the explanation thereof is omitted, and the points different from the first embodiment or the second embodiment will be explained.

FIG. 5 is a longitudinal sectional view of speaker 1201 according to the first modification of the second embodiment of the present disclosure.

A speaker 1201 according to the first modification of the second embodiment of the present disclosure includes a first exterior case 1202 as an example of a base, a second exterior case 1223, a magnetic circuit section 203, a lid section 1204, and a voice coil. 5.

The first exterior case 1202 is formed in the shape of an open container. The first exterior case 1202 has a peripheral wall portion 21 and a bottom portion 1222 . The peripheral wall portion 21 is formed integrally with the bottom portion 1222 and has one end connected to the peripheral portion of the bottom portion 1222 . A plurality of recesses 21a capable of accommodating screw heads are provided on the inner peripheral surface of the peripheral wall 21 on the other end side. The bottom portion 1222 is provided with a plurality of through holes 1202h.

The second exterior case 1223 is formed in the shape of an open container. The second exterior case 1223 is arranged to cover the first exterior case 1202 . The second exterior case 1223 has air holes 9 that allow air to flow between the inside and outside of the second exterior case 1223 . Air holes 9 are provided with a known polymeric material. The second exterior case 1223 defines a space together with the first exterior case 1202 . Air can flow between the defined space and the inner space of the first exterior case 1202 through the plurality of through holes 1202h.

The lid portion 1204 is attached to the first exterior case 1202 and the second exterior case 1223 so as to block the opening of the first exterior case 1202 and the opening of the second exterior case 1223 . More specifically, the lid portion 1204 has a diaphragm 1241 as an example of a vibrating portion, a holding frame 1242 that holds the diaphragm 1241 , and pads 1243 provided on the diaphragm 1241 .

Diaphragm 1241 is formed in the shape of an elastically deformable plate. Diaphragm 1241 is made of stainless steel, but may be made of, for example, steel, titanium, aluminum, tile material, wood, or heat-resistant resin (for example, mixed resin in which carbon is mixed with resin). may Alternatively, diaphragm 1241 may be made of an elastic member. Diaphragm 1241 has an arbitrary thickness such that speaker 1201 can produce a predetermined sound pressure. A connection member 451 is connected to the central portion of the diaphragm 1241 .

The holding frame 1242 is formed in a cylindrical shape. The holding frame 1242 is attached to the peripheral wall portion 21 so that there is no gap between one end portion of the holding frame 1242 and the other end portion of the peripheral wall portion 21 . The peripheral edge of diaphragm 1241 is connected to the other end of holding frame 1242 so that no gap is formed between the other end of holding frame 1242 and the peripheral edge of diaphragm 1241 .

The pad 1243 is arranged on the side opposite to the connecting member 451 with respect to the diaphragm 1241 and connected to the diaphragm 1241 . This pad 1243 contacts the user's skin when the speaker 1201 is in use.

The speaker 1201 configured in this way functions, for example, as a bone conduction speaker capable of transmitting the vibration of the diaphragm 1241 to the user's cochlea via the pad 1243 or the like. It also functions as a waterproof wireless speaker, for example, using a wireless device such as a transceiver.

(Second modification)
A speaker 2201 according to the second modification of the second embodiment of the present disclosure has a water sensor 2281 that detects water attached to an exterior case 2202, and a control unit 2282 and a power supply unit 2283 in the exterior case 2202. is accommodated in the first embodiment, the second embodiment, or the first modification of the second embodiment. In addition, in this modified example, the same reference numerals are given to the same parts as those in the first modified example of the first embodiment, the second embodiment, or the second embodiment, and the description thereof is omitted. Differences from the embodiment or the first modification of the second embodiment will be described.

FIG. 6 is a vertical cross-sectional view of a speaker 2201 according to a second modified example of the second embodiment of the present disclosure.

A speaker 2201 according to the second modification of the second embodiment of the present disclosure includes an exterior case 2202 as an example of a base, a magnetic circuit unit 203, a diaphragm 2241, a voice coil 5, a water sensor 2281, a control A unit 2282 and a power supply unit 2283 are provided.

The exterior case 2202 is formed to imitate the shape of a fish.

The magnetic circuit unit 203 is housed in an exterior case 2202 and attached to the exterior case 2202 . More specifically, the magnetic circuit section 203 is housed in a closed space defined by the exterior case 2202 and a diaphragm 2241, which will be described later. An electric signal line 2208 of a control unit 2282 to be described later is electrically connected to the magnetic circuit unit 203 .

Diaphragm 2241 is formed to be convex from the head side to the tail side of a fish. In the present embodiment, the diaphragm 2241 is made of stainless steel. may be formed. Alternatively, diaphragm 2241 may be made of an elastic member. Diaphragm 2241 has an arbitrary thickness such that speaker 2201 can produce a predetermined sound pressure. A connection member 451 is connected to the central portion of the diaphragm 2241 .

Water sensor 2281 is attached to the outer surface of exterior case 2202 . A water sensor 2281 is connected to the control unit 2282 and can detect that the speaker 2201 is underwater.

The control unit 2282 is electrically connected to the magnetic circuit unit 203 and the power supply unit 2283 inside the exterior case 2202 . The control unit 2282, for example, D/A (digital-analog) converts the sound signal stored in the memory in a CPU (Central Processing Unit) and outputs it to the voice coil 5 from the amplifier. When the water sensor 2281 detects that the speaker 2201 is in the water, the control unit 2282 controls the speaker 2201 so that it emits, for example, the sound of a school of fish eating food.

For example, when the speaker 2201 configured in this manner generates sound pressure in a low-frequency sound range of 10 Hz to 400 Hz by generating low-frequency sound vibration, By resonating the voice coil 5 and the magnetic circuit unit 203, it functions as a lure for artificial bait that emits a sound wave for attracting fish.

According to the speaker of this embodiment, the following effects are obtained.

Since the second magnet 234 is arranged inside the voice coil 5 in the radial direction, it is possible to suppress an increase in the size of the speaker 201 in the axial direction.

In addition, by arranging the second magnet 234 radially inward of the voice coil 5 , it is possible to prevent the empty space radially outward of the voice coil 5 from becoming smaller. Therefore, the degree of freedom in designing the radially outer side of the voice coil 5 can be increased.

Also, the second magnet 234 does not hinder the increase in the diameter of the voice coil 5 . Therefore, it becomes easy to increase the excitation force of the voice coil 5 by increasing the diameter of the voice coil 5 .

Further, according to a modification of this embodiment, the air holes 9 are provided with a known polymeric material to allow air to flow. Therefore, even if the speaker 1201 is affected by water pressure, soil pressure, atmospheric pressure, or temperature, expansion or contraction of the speaker 1201 can be suppressed.

(Third Embodiment)
In a speaker 301 according to the third embodiment of the present disclosure, a peripheral wall portion 321 of an exterior case 302 has a first peripheral wall portion 321a and a second peripheral wall portion 321b, a bottom portion 322 has an air hole 9, and a magnetic circuit portion 303 In that the second magnet 334 of has the third magnet 35 and the fourth magnet 36, the first embodiment, the second embodiment, the first modification of the second embodiment, or the second modification of the second embodiment is different from In addition, the speaker 301 according to the third embodiment of the present disclosure further includes a third elastic member 64 and a rod member 72, and the diaphragm 3041 is attached to the peripheral wall portion 321 without a holding frame. This is different from the first and second embodiments. Furthermore, the speaker 301 according to the third embodiment of the present disclosure differs from the second embodiment in that a compression spring 71 is provided. In addition, in the third embodiment, the same reference numerals are given to the same parts as in the first embodiment, the second embodiment, the first modification of the second embodiment, or the second modification of the second embodiment. are omitted, and differences from the first embodiment, the second embodiment, the first modification of the second embodiment, or the second modification of the second embodiment will be described.

FIG. 7 is a longitudinal sectional view of speaker 301 according to the third embodiment of the present disclosure.

The peripheral wall portion 321 has a first peripheral wall portion 321a and a second peripheral wall portion 321b.

The first peripheral wall portion 321a is formed in a cylindrical shape and protrudes radially inward of the voice coil 5 from an intermediate portion to one end portion in a direction parallel to the axial direction of the voice coil 5. ing.

The second peripheral wall portion 321b is formed in a cylindrical shape, and is arranged side by side on the voice coil 5 side of the portion of the first peripheral wall portion 321a protruding radially inward of the voice coil 5 . The first peripheral wall portion 321 a is formed integrally with the bottom portion 322 . One ends of the first peripheral wall portion 321a and the second peripheral wall portion 321b are connected to the peripheral edge portion of the bottom portion 322, respectively.

The bottom portion 322 has an air hole 9 for circulating air between the inside and the outside of the speaker 301 . Air holes 9 are provided with a known polymeric material.

The second magnet 334 of the magnetic circuit section 303 has a third magnet 35 arranged radially outside the voice coil 5 and a fourth magnet 36 arranged radially inside the voice coil 5 .

The third magnet 35 is arranged on the side opposite to the first flange portion 311 with respect to the second yoke 32 and attached to the second yoke 32 . More specifically, the third magnet 35 is formed in an annular shape and has an inner peripheral surface facing a portion of the voice coil 5 with a gap therebetween. The third magnet 35 overlaps the first magnet 33 in the axial direction of the voice coil 5 . The magnetic pole of the third magnet 35 has an S pole on the second yoke 32 side over the entire circumference, and an N pole on the diaphragm 3041 side, which will be described later, over the entire circumference. The south pole of the third magnet 35 is in contact with the first surface 32 a of the second yoke 32 . On the other hand, the north pole of the third magnet 35 faces the space inside the diaphragm 3041 .

The fourth magnet 36 is arranged radially inside the voice coil 5 . More specifically, the fourth magnet 36 is arranged radially inside the voice coil 5 on the side opposite to the first flange portion 311 with respect to the column portion 312 and on the second end portion 312b side of the column portion 312. and the first surface 313 a of the second flange portion 313 . More specifically, the fourth magnet 36 is formed in an annular shape, and its outer peripheral surface faces a part of the voice coil 5 with a gap therebetween. The magnetic pole of the fourth magnet 36 has an N pole on the side of the column portion 312 or the second flange portion 313 over the entire circumference, and an S pole on the side of the diaphragm 3041 over the entire circumference. The N pole of the fourth magnet 36 is in contact with the end surface of the column portion 312 on the second end portion 312 b side and the first surface 313 a of the second flange portion 313 . On the other hand, the south pole of the fourth magnet 36 faces the space inside the diaphragm 3041 .

Diaphragm 3041 is formed in the shape of an elastically deformable plate. The diaphragm 3041 also serves as a lid that closes the opening of the exterior case 302 . A peripheral edge portion of the diaphragm 3041 is attached to the peripheral wall portion 321 so as not to form a gap with the other end portion of the peripheral wall portion 321 . In this embodiment, the diaphragm 3041 is made of ceramic, but may be made of, for example, steatite, stainless steel, aluminum, or hard heat-resistant resin. Alternatively, diaphragm 3041 may be made of heat-resistant plastic. The thickness of the diaphragm 3041 is, for example, 2 mm or more so that the speaker 301 can generate a sound pressure of 10 dB or more even when an external force of several hundred kg acts on the speaker 301 due to water pressure or earth pressure. It can be thick.

A rod member 72 is arranged inside the through hole 31 h of the column portion 312 and the compression spring 71 . The rod member 72 is arranged such that the central axis of the rod member 72 is parallel to the central axis of the voice coil 5 . One end of the rod member 72 on the side of the lid portion 4 is attached to the connecting member 451 . For example, when the diaphragm 3041 receives water pressure from the outside of the speaker in water at a depth of about 10 m, and the diaphragm 3041 is pushed into the speaker 301, the bar member 72 moves toward the bottom 322 of the exterior case 302. do.

The third elastic member 64 is attached to the end surface of the column portion 312 on the one end side so as to cover the through hole 31h of the column portion 312 . The other end of the rod member 72 is attached to the third elastic member 64 . That is, the third elastic member 64 sandwiches the rod member 72 together with the connecting member 451 . For example, when the speaker 1 receives water pressure from the outside in water at a depth of about 10 m, and the diaphragm 3041 is pushed into the speaker 301, the third elastic member 64 will not move the rod member 72 attached to the bottom 322. Since it moves to the side, it moves to the bottom 322 side of the exterior case 302 . Therefore, the magnetic circuit portion 303 attached to the third elastic member 64 moves toward the bottom portion 322 of the exterior case 302 .

(Operation of speaker 301)
FIG. 8 is a partially enlarged view schematically showing the magnetic flux generated in the magnetic circuit section 303 of the speaker 301 shown in FIG.

In this embodiment, the first magnet 33 forms the first magnetic flux 331 , and the third magnet 35 and the fourth magnet 36 form the third magnetic flux 351 and the fourth magnetic flux 361 . When the first magnet 33, the third magnet 35 and the fourth magnet 36 are arranged as shown in FIGS. 7 and 8, the first magnetic flux 331 formed by the first magnet 33 is and the third magnetic flux 351 and the fourth magnetic flux 361 formed by the third magnet 35 and the fourth magnet 36 are added. Therefore, the magnetic flux that contributes to the axial vibration of the voice coil increases compared to the case where the magnetic circuit section does not have the third magnet and the fourth magnet. At this time, the magnetic flux density of the magnetic flux directed to the voice coil 5 is increased by, for example, 40% or more compared to the case where the magnets arranged in the magnetic circuit portion are only the first magnets. Further, the increased excitation force can increase the output sound volume of the speaker 301 by, for example, 6 dB or more, preferably 10 dB or more, and more preferably 12 dB or more.

(First modification)
In a speaker 2301 according to the first modification of the third embodiment of the present disclosure, a peripheral wall portion 2321 and a bottom portion 2322 of an exterior case 2302 are screwed together, and an O-ring 2374 sealing between the peripheral wall portion 2321 and the bottom portion 2322 is provided. A second elastic member 2362 is connected to the middle portion of the voice coil 5, the rod member 2372 is rotatable forward and backward about the axis of the rod member 2372, and a support plate 2373 associated with the rod member 2372 is arranged. This embodiment differs from the first embodiment, the second embodiment, the first modification of the second embodiment, the second modification of the second embodiment, or the third embodiment in that Moreover, it differs from the third embodiment in that the air holes 9 are omitted. In addition, in this modified example, the same reference numerals are given to the same parts as in the first embodiment, the second embodiment, the first modified example of the second embodiment, the second modified example of the second embodiment, or the third embodiment. Description will be omitted, and differences from the first embodiment, the second embodiment, the first modification of the second embodiment, the second modification of the second embodiment, or the third embodiment will be described.

FIG. 9 shows a first modification of the third embodiment. This modification can also be applied to the first embodiment, the second embodiment, the first modification of the second embodiment, or the second modification of the second embodiment. FIG. 9 is a longitudinal sectional view of a speaker 2301 according to the first modified example of the third embodiment. In FIG. 9, illustration of the electric signal line 8 is omitted.

The peripheral wall portion 2321 is configured such that one end portion and an intermediate portion protrude radially inwardly of the voice coil 5 , and the intermediate portion protrudes radially inwardly of the voice coil 5 more than the one end portion. ing. The intermediate portion has a surface facing the bottom portion 2322 . The peripheral wall portion 2321 has, at one end portion thereof, a recess for accommodating an O-ring 2374, which will be described later.

The bottom portion 2322 is screwed to the peripheral wall portion 2321 . The bottom portion 2322 has a recess in the peripheral portion of the bottom portion 2322 to accommodate the O-ring 2374 in a pair with the recess provided at one end of the peripheral wall portion 2321 .

An O-ring 2374, which is an example of a sealing member, is accommodated in the recess of the peripheral wall portion 2321 and the recess of the bottom portion 2322, and provided to seal between one end portion of the peripheral wall portion 2321 and the peripheral portion of the bottom portion 2322. .

The second elastic member 2362 is formed separately from the connecting member 451 and connected to the magnetic circuit section 3 and the voice coil 5 . More specifically, one end of the second elastic member 2362 on the voice coil 5 side is connected to the intermediate portion 451 b of the bobbin portion 51 in the axial direction of the voice coil 5 . The other end of the second elastic member 2362 on the side of the magnetic circuit section 3 is connected to the first surface 32 a of the second yoke 32 via a plurality of spacers 63 .

The compression spring 71 is sandwiched between the connecting member 451 and an end face of a bar member 2372 (to be described later) on the diaphragm 3041 side. The compression spring 71 is attached to the connecting member 451 with an adhesive.

One end of the rod member 2372 on the side of the diaphragm 3041 is formed into a flange shape, and is in slidable contact with the compression spring 71 . The rod member 2372 is provided with a male threaded portion at the other end portion on the bottom portion 2322 side. The rod member 2372 can rotate forward and backward around the axis of the rod member 2372 .

Between the magnetic circuit portion 303 and the bottom portion 2322, a support plate 2373 formed in a hard disc shape and attached to the surface facing the bottom portion 2322 in the intermediate portion of the peripheral wall portion 2321 is arranged. The support plate 2373 is provided with a female threaded portion that engages with the male threaded portion of the rod member 2372 at the center portion in the radial direction of the support plate 2373 .

As a result, when the rod member 2372 is rotated in forward and reverse directions around the axis of the rod member 2372, the male threaded portion of the rod member 2372 and the female threaded portion of the support plate 2373 engage with each other. The vibration plate 3041 can be supported via the compression spring 71 while moving forward and backward.

(Second modification)
A speaker 1301 according to the second modification of the third embodiment of the present disclosure differs from the first embodiment and the second embodiment in that the vibrating portion 1341 accommodates the base 1302, the magnetic circuit portion 303, and the voice coil 5. It differs from the form, the first modification of the second embodiment, the second modification of the second embodiment, the third embodiment, or the first modification of the third embodiment. Moreover, it differs from the third embodiment in that the air holes 9 are omitted. In addition, in this modification, the first embodiment, the second embodiment, the first modification of the second embodiment, the second modification of the second embodiment, the third embodiment, or the first modification of the third embodiment. The same reference numerals are given to the same parts as in the modification, and the description is omitted. Differences from the embodiment or the first modification of the third embodiment will be described.

FIG. 10 shows a second modification of the third embodiment. This modification can also be applied to the first embodiment, the second embodiment, the first modification of the second embodiment, the second modification of the second embodiment, or the first modification of the third embodiment. . FIG. 10 is a longitudinal sectional view of speaker 1301 according to the second modification of the third embodiment. In FIG. 10, illustration of the electric signal line 8 is omitted.

Speaker 1301 includes vibrating portion 1341 , base 1302 , magnetic circuit portion 303 , and voice coil 5 .

The vibrating section 1341 is a cylinder housing the base 1302 , the magnetic circuit section 303 and the voice coil 5 . The vibrating portion 1341 also serves as an exterior case for the speaker 1301 . The vibrating portion 1341 is formed to be elastically deformable. The vibrating portion 1341 has lid members (not shown) closing the opening of the cylinder at both ends in the axial direction. That is, the magnetic circuit section 303 is accommodated in the closed space formed by the vibrating section 1341 .

The base 1302 has a first end portion 1302a located on one radial side of the cylinder of the vibrating portion 1341 and a second end portion 1302b located on the other radial side of the cylinder of the vibrating portion 1341 . In this modification, the base 1302 further has a third end 1302c in the radial direction of the cylinder of the vibrating portion 1341, separate from the first end 1302a and the second end 1302b. A first end portion 1302 a of the base 1302 is fixed to an inner peripheral surface 1341 a on one side in the radial direction of the cylindrical body of the vibrating portion 1341 . A second end portion 1302b of the base 1302 is fixed to an inner peripheral surface 1341a on the other side in the radial direction of the cylinder of the vibrating portion 1341 . In this modified example, the third end portion 1302c of the base 1302 is fixed to an inner peripheral surface 1341a different from the one side and the other side in the radial direction of the cylinder of the vibrating portion 1341 . The connecting member 451 is attached to the inner peripheral surface 1341a of the cylinder of the vibrating section 1341 on the side opposite to the third end 1302c of the base 1302 in the radial direction of the cylinder of the vibrating section 1341 .

According to the speaker of this embodiment, the following effects are obtained.

Compared to the first embodiment, the magnetic poles of the first magnet 33, the third magnet 35, and the fourth magnet 36 are arranged so that the magnetic flux toward the voice coil 5 is further increased. In comparison, the excitation force of the voice coil 5 can be further increased to increase the sound pressure. With this arrangement, compared to the second embodiment, the excitation force of the voice coil 5 can be increased by 10%, for example, and the sound pressure can be increased.

Further, since the third magnet 35 is arranged radially outside the voice coil 5, it is possible to suppress an increase in the size of the speaker 301 in the axial direction.

Further, by arranging the third magnet 35 radially outside the voice coil 5 , the radial size of the third magnet 35 can be made larger than the outer diameter of the voice coil 5 . Therefore, compared to the case where the third magnet is arranged radially inside the voice coil 5, the magnetic flux contributing to the axial vibration of the voice coil 5 can be increased.

Further, since the fourth magnet 36 is arranged radially inside the voice coil 5, it is possible to suppress an increase in the size of the speaker 301 in the axial direction.

In addition, by arranging the fourth magnet 36 radially inward of the voice coil 5 , it is possible to prevent the empty space radially outward of the voice coil 5 from becoming smaller. Therefore, the degree of freedom in designing the radially outer side of the voice coil 5 can be increased.

Further, the third magnet 35 and the fourth magnet 36 can reduce the weight difference between the radially outer portion of the magnetic circuit portion 303 and the radially inner portion of the magnetic circuit portion 303 .

Further, the weight of the magnetic circuit unit 303 is increased by the third magnet 35 and the fourth magnet 36 to adjust the resonance frequency, thereby facilitating the production of bass sounds.

Further, for example, when the speaker 301 receives water pressure from the outside in water at a depth of about 10 m, the compression spring 71, the rod member 72, and the third elastic member 64 move the magnetic circuit portion 303 toward the bottom portion 322 side of the exterior case 302. By applying the positive force, the relative positional relationship between the magnetic circuit section 303 and the voice coil 5 can be easily maintained, and a decrease in the Lorentz force applied to the voice coil 5 can be suppressed. Therefore, a decrease in the sound pressure emitted by the speaker 301 can be suppressed.

Further, since the bottom portion 322 has the air hole 9 for circulating air between the inside and the outside of the speaker 301, for example, when the speaker 301 comes into contact with high-temperature outside air on the ground, the air inside the speaker 301 expands. However, the air inside the speaker 301 can be discharged to the outside of the speaker 301 through the air hole 9 .

Further, according to the modified example of the present embodiment, the rod member 2372 supporting the diaphragm 3041 via the compression spring 71 moves back and forth in the axial direction of the voice coil 5, for example, in water deeper than 10 m deep. When the speaker 2301 receives water pressure from the outside, it is possible to prevent the diaphragm 3041 from bending toward the inside of the speaker 2301 and being damaged by the external pressure.

Further, according to the modification of the present embodiment, the first end portion 1302a and the second end portion 1302b of the base 1302 are fixed to the inner peripheral surface 1341a of the vibrating portion 1341, so that the vibrating portion can be moved from the inside of the vibrating portion 1341. 1341 can be supported by base 1302 to reinforce vibrating portion 1341 . Therefore, for example, the speaker 1301 can be used in water deeper than 100 m.

In the above embodiment and modifications, the second magnet 34 or the third magnet 35 is arranged so as to overlap the first magnet 33 in the axial direction of the voice coil 5; It may be arranged radially outside the coil 5 so as not to overlap the first magnet 33 in the axial direction of the voice coil 5 .

In the above-described embodiment and modified example, the first flange portion 311 and the second flange portion 313 are respectively provided over the entire circumference in the circumferential direction around the central axis of the column portion 312. good.

Although the first magnet 33, the second magnet 34, the second magnet 234, the third magnet 35, and the fourth magnet 36 are each formed in an annular shape in the above-described embodiment and modification, they may be in an angular annular shape.

In the above-described embodiment and modification, the second magnet 234 or the fourth magnet 36 arranged radially inward of the voice coil 5 is positioned between the end surface of the column portion 312 on the second end portion 312b side and the first flange portion 313 of the second flange portion 313 . Although it is attached to the surface 313a, it may be attached only to at least one of the end face of the column portion 312 on the second end portion 312b side and the first surface 313a of the second flange portion 313. FIG.

Although the diaphragm 41 and the connection member 451 are attached in point contact in the above-described embodiment and modification, they may be attached in surface contact with a larger contact area than the point contact. The resonance point can be changed by changing the contact area between the diaphragm and the connection member. For example, when installing such a speaker on the surface of water or on the ground, the diaphragm and the connecting member may be in surface contact.

Although the compression spring 71 is fixed to the connection member 451 or the column portion 312 with an adhesive in the above-described embodiment and modification, it may be brought into contact without using an adhesive.

In the above-described embodiment and modifications, the speaker 1201 functions as a bone conduction speaker capable of transmitting sound by vibrating the skull by contacting the skin. It may be attached to a formed wall to function as a bone conduction speaker or a relaxation vibroacoustic speaker.

In the above-described embodiment and modification, the speaker 2201 functions as a lure that emits a sonic fish attracting sound by low-frequency sonic vibration, but a lure that emits a sonic repelling sound so that the fish moves away from the lure. May function as a lure. The speaker according to the present invention may also be used, for example, in hydroponic cultivation of leafy vegetables by means of low-frequency sound wave vibrations.

Although the speaker 2201 includes the magnetic circuit section 203 in the above-described embodiment and modification, the magnetic circuit section 303 may be included. Further, the rod member 72 and the third elastic member 64 may be further provided according to the depth of water where the speaker 2201 is arranged. By configuring in this way, the speaker 2201 can be used in deeper water.

In the above-described embodiment and variations, the compression spring 71 is attached to the connecting member 451 with an adhesive and slidably abuts the rod member 2372, but slidably abuts the connecting member 451 and is in contact with the rod member. 2372 may be adhesively attached.

In the above embodiments and modified examples, it was shown that the speaker according to the present invention can be used in various applications. It can also be used as various devices or microphones, such as a ceiling panel speaker, a bathtub case floor vibration speaker, a bench speaker, a vehicle-mounted side or ceiling speaker, a general acoustic speaker, or a massage machine. The speaker according to the present invention is suitable for use in environments requiring pressure resistance, water resistance, or waterproofness.

In the above embodiments and modifications, the speaker functions as an underwater speaker, but may function as a speaker for use on land.

By appropriately combining any of the various embodiments or modifications described above, the respective effects can be obtained. In addition, combinations of embodiments, combinations of examples, or combinations of embodiments and examples are possible, as well as combinations of features in different embodiments or examples.

Reference Signs List 1 speaker 2 exterior case 3 magnetic circuit section 5 voice coil 31 first yoke 32 second yoke 33 first magnet 34 second magnet 35 third magnet 36 fourth magnet 41 diaphragm 201 speaker 203 magnetic circuit section 234 second magnet 301 Speaker 302 Exterior case 303 Magnetic circuit 311 First flange 312 Column 312a First end 312b Second end 313 Second flange 331 First magnetic flux 334 Second magnet 341 Second magnetic flux 351 Third magnetic flux 361 Fourth Magnetic flux 1201 Speaker 1202 First exterior case 1223 Second exterior case 1241 Diaphragm 1301 Speaker 1302 Base 1302a First end 1302b Second end 1302c Third end 1341 Vibration part 1341a Inner surface 2201 Speaker 2202 Exterior case 2241 Diaphragm 2341 second magnetic flux 3041 diaphragm

A speaker according to one aspect of the present invention includes
a base;
a magnetic circuit unit attached to the base via an elastic member ;
a vibrating portion covering the magnetic circuit portion;
a voice coil connected to the vibrating portion and positioned between the vibrating portion and the magnetic circuit;
The magnetic circuit unit is
a first yoke having a column portion and a flange portion provided at an end portion of the column portion opposite to the vibrating portion;
a second yoke provided around an end portion of the column portion on the vibrating portion side such that a gap for inserting the voice coil is formed between the column portion and the first yoke;
a first magnet sandwiched between the flange portion and the second yoke;
a second magnet disposed on the side opposite to the flange portion with respect to at least one of the column portion and the second yoke so as to increase magnetic flux toward the voice coil ;
The base has a peripheral wall portion surrounding the magnetic circuit portion,
The elastic member has a main body attached to the second yoke, and a plurality of arms protruding from the outer peripheral edge of the main body and attached to the peripheral wall of the base.

Claims (6)

a base;
a magnetic circuit unit attached to the base;
a vibrating portion covering the magnetic circuit portion;
a voice coil connected to the vibrating portion and positioned between the vibrating portion and the magnetic circuit;
The magnetic circuit unit is
a first yoke having a column portion and a flange portion provided at an end portion of the column portion opposite to the vibrating portion;
a second yoke provided around an end portion of the column portion on the vibrating portion side such that a gap for inserting the voice coil is formed between the column portion and the first yoke;
a first magnet sandwiched between the flange portion and the second yoke;
and a second magnet disposed on the side opposite to the flange portion with respect to at least one of the column portion and the second yoke so as to increase the magnetic flux toward the voice coil. The speaker according to claim 1,
The speaker, wherein the second magnet is arranged radially outward of the voice coil. The speaker according to claim 2,
The speaker, wherein the second magnet overlaps the first magnet in the axial direction of the voice coil. The speaker according to claim 1,
The speaker, wherein the second magnet is arranged radially inside the voice coil. The speaker according to claim 1,
The speaker, wherein the second magnet has a third magnet arranged radially outside the voice coil and a fourth magnet arranged radially inside the voice coil. In the speaker according to any one of claims 1 to 5,
The vibrating portion is a cylinder housing the base, the magnetic circuit portion, and the voice coil,
The base has a first end located on one side in the radial direction of the cylinder and a second end located on the other side in the radial direction of the cylinder,
The first end is fixed to the inner peripheral surface on one side in the radial direction of the cylindrical body,
The speaker, wherein the second end is fixed to the inner peripheral surface of the cylindrical body on the other side in the radial direction.

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