WO2013190811A1

WO2013190811A1 - Speaker device and speaker-equipped device

Info

Publication number: WO2013190811A1
Application number: PCT/JP2013/003732
Authority: WO
Inventors: 松村　俊之; 佐伯　周二; 佐和子狩野; 明子藤瀬; 敦坂口
Original assignee: パナソニック株式会社
Priority date: 2012-06-21
Filing date: 2013-06-13
Publication date: 2013-12-27

Abstract

Provided is a speaker device that is configured so as to include a magnetic circuit having a magnetic gap, a voice coil (6) that is at least partially positioned in the magnetic gap, a diaphragm (4) to which the voice coil (6) is fixed, multiple supports (5) for supporting the diaphragm (4), and a magnetic fluid (7) that is provided on the inner periphery and/or the outer periphery of the voice coil (6). The magnetic circuit is configured so as to include at least multiple magnets (2a, 2b), a yoke (3), and a plate (1). The magnetic circuit has a through hole (T), which penetrates in the vibrating direction of the diaphragm (4), on the inner side of the voice coil (6).

Description

Speaker device and speaker mounting device

The present invention relates to a speaker device, a speaker-mounted device such as an audiovisual apparatus or a portable information processing device including the speaker device, and more specifically, a small speaker device capable of wide-band reproduction, and the speaker device. The present invention relates to an audiovisual apparatus, a portable information processing apparatus including the speaker device, a moving unit, and an inner phone.

In recent years, miniaturization and high functionality of audiovisual equipment, so-called AV equipment, are rapidly progressing. This is particularly true for mobile phones, smartphones, tablet PC (personal computer) terminals, etc., but since miniaturization and high functionality are advancing at the same time, smaller and thinner devices are required for installed devices. . The speaker mounted on each device is no exception, and it is required to be small and thin like other devices. However, the downsizing of the speaker leads to deterioration of the reproduction capability, particularly the reproduction frequency band and the reproduction efficiency. Therefore, there is a limit to the size reduction and reproduction capability of the conventional technology.

Therefore, as a conventional technique, there is a speaker in which a magnetic fluid is arranged in a magnetic circuit and a speaker reproduction band is improved (for example, see Patent Document 1). FIG. 11 is a diagram showing a conventional speaker described in Patent Document 1. In FIG. Each cross-sectional view (end view by AOB line, end view by MN line) means an arrow view, and members not on the end face are appropriately indicated by virtual lines. The speaker shown in FIG. 11 has a voice coil 116 disposed in a magnetic circuit composed of a magnet 111, a plate 112, and a yoke 110, and drives a diaphragm 113. The magnetic fluid 117 is disposed between the outer peripheral portion of the plate 112 and the inner peripheral portion of the voice coil 116, and by separating the space on the front surface of the diaphragm 113 from the space on the rear surface, sound generated from the front surface and The structure is such that the generated sound is prevented from canceling, the rolling vibration of the diaphragm 113 is prevented, and the Joule heat generated by the voice coil 116 is released to the magnetic circuit. Further, by supporting the diaphragm 113 with the plurality of

edge portions

114a, 114b, 114c, and 114d together with the magnetic fluid 117, the support that works on the diaphragm 113 compared to the case where the entire outer periphery of the diaphragm 113 is configured with edges. The system compliance has been increased, and low frequency reproduction is possible even with a small aperture.

International Publication No. 2009/066415

The sound generated from the rear surface of the diaphragm 113 of the speaker configured as in Patent Document 1 is released toward the lower surface of the speaker through a hole U opened in the plate 112, the magnet 111, and the yoke 110. The presence of the hole U can be expected to prevent the movement of the diaphragm from being braked by the compliance of air confined on the back surface of the diaphragm 113. Therefore, it may be preferable that the hole U is provided in the magnet, the plate, and the yoke.

However, if the device becomes smaller, it becomes difficult to form a hole in the magnet due to problems during magnet manufacture. For example, when shrinking during magnet sintering, stress is generated around the hole, causing cracks and the like. FIG. 11 shows an example in which an annular magnet is used, but an ellipse or a track shape (a shape composed of two parallel line segments and two curves connecting opposite ends of the line segments). In this case, it is more difficult to manufacture a magnet with a hole. Also, there is a method of making a hole in a magnet without a hole, but when making a hole in a small magnet, the magnet is easily broken when making the hole, and it is difficult to manufacture stably. In addition, the manufacturing cost increases.

Therefore, the present disclosure provides a speaker device that is easy to mount and can be reproduced in a small size and a wide band.

In order to solve the conventional problems, a speaker device of the present disclosure includes a magnetic circuit having a magnetic gap, a voice coil at least partially disposed in the magnetic gap, and a diaphragm to which the voice coil is fixed. And a plurality of supports that support the diaphragm, and a magnetic fluid disposed on at least one of the inner and outer peripheral portions of the voice coil, and the magnetic circuit includes at least a plurality of magnets and a yoke And the plate, and the magnetic circuit has a through-hole penetrating in the vibration direction of the diaphragm inside the voice coil.

In the speaker device of the present disclosure, since a magnetic circuit is configured by combining a plurality of magnets, the size and slim shape of the speaker can be determined without being limited to the manufacturing process, such as cracking during firing, and it is easier to mount. It is possible to provide a speaker device that is small and capable of reproducing in a wide band.

FIG. 1A is a top view and a cross-sectional view of a structure of a first speaker device according to the present disclosure. FIG. 1B is a top view and a cross-sectional view of a first speaker device according to another configuration. FIG. 1C is a top view and a cross-sectional view of a first speaker device according to still another configuration. FIG. 2 is a structural cross-sectional view of a first speaker device according to still another configuration. FIG. 3 is a top view and a structural cross-sectional view of a second speaker device according to the present disclosure. FIG. 4A is a structural cross-sectional view of a third speaker device according to the present disclosure. FIG. 4B is a structural cross-sectional view of a third speaker device according to another configuration. FIG. 5 is a structural cross-sectional view of a fourth speaker device according to the present disclosure. FIG. 6A is a structural cross-sectional view of a fifth speaker device according to the present disclosure. FIG. 6B is a structural cross-sectional view of a fifth speaker device according to another configuration. FIG. 6C is a structural cross-sectional view of a fifth speaker device according to still another configuration. FIG. 7 is a mobile information terminal device according to the present disclosure. FIG. 8 is an image display device according to the present disclosure. FIG. 9 is a mounting diagram of the in-vehicle speaker according to the present disclosure. FIG. 10 is a structural cross-sectional view of the inner phone according to the present disclosure. FIG. 11 is a top view and a cross-sectional view of a conventional speaker.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. In the following, the terms “outer” and “inner” are used in the direction orthogonal to the axial direction of the voice coil. Each cross-sectional view (an end view taken along line AB and an end view taken along line MN) means an arrow view, and members not on the end face are appropriately indicated by virtual lines.

The present disclosure relates to a magnetic circuit having a magnetic gap, a voice coil at least partially disposed in the magnetic gap, a diaphragm to which the voice coil is fixed, and a plurality of supports that support the diaphragm. And a magnetic fluid disposed on at least one of an inner peripheral portion and an outer peripheral portion of the voice coil, and the magnetic circuit includes at least a plurality of magnets, a yoke, and a plate, and the magnetic circuit The circuit includes a speaker device having a through-hole penetrating in the vibration direction of the diaphragm inside the voice coil. According to this configuration, since a magnetic circuit is configured by combining a plurality of magnets, it is possible to determine the size and slim shape of the device without being bound to the manufacturing process, such as cracking during firing, and it is easier to mount. It is possible to provide a speaker device that can be reproduced in a small size and a wide band.

Also, as another aspect of the speaker device, it is possible to adopt the following configuration.

For example, the magnetic fluid may be disposed only on the yoke side of the voice coil. According to this configuration, in the case where an internal magnetic circuit is employed, the magnetic fluid is formed in the gap between the magnets, which is generated when it is assumed that the magnetic fluid is disposed on the plate side inside the voice coil. Can be prevented from being sucked by capillary action.

Further, for example, the magnetic fluid is disposed at least on the plate side of the voice coil, and the magnetic circuit fills at least a yoke, a plate, the plurality of magnets, and a boundary region between the plurality of magnets. It may be configured to include a filling member. According to this configuration, the gap between the magnets can be eliminated by the filling member to prevent the spaces before and after the diaphragm from being connected, and the magnetic fluid can be prevented from entering the gap between the magnets due to capillary action. . For this reason, the speaker device can operate with stable performance.

Also, for example, the magnetic fluid is disposed at least on the plate side of the voice coil, and the magnetic circuit is at least a yoke, a plate, and the plurality of magnets disposed outside the through hole, A first cover member that covers at least a boundary region between the plurality of magnets from the inside of the plurality of magnets may be included. According to this configuration, since the gap between the magnets and the through hole can be separated by the first cover member, the space before and after the diaphragm is connected, and sound cancellation before and after the diaphragm occurs. Can be prevented.

Further, for example, the first cover member may have a protruding portion that protrudes on the surface of the magnetic circuit component member that surrounds one or both through ends of the through hole. According to this structure, since the 1st cover member has an overhang | projection part, the 1st cover member can be used as a jig | tool which can position an other member easily at the time of manufacture of a speaker apparatus. For this reason, it becomes possible to separate the space before and behind the diaphragm with higher accuracy.

Also, for example, the magnetic fluid is disposed at least on the plate side of the voice coil, and the magnetic circuit is at least a yoke, a plate, and the plurality of magnets disposed outside the through hole, A second cover member that covers a boundary region between the plurality of magnets from the outside of the plurality of magnets may be included. According to this configuration, the second cover member separates the outside of the plurality of magnets from the gaps and through holes between the magnets. Therefore, it is possible to prevent the spaces before and after the diaphragm from being connected and canceling the sound before and after the diaphragm.

Further, for example, the magnetic fluid is disposed on both the yoke side and the plate side of the voice coil, and communicates the space surrounded by the magnetic fluid, the voice coil, the yoke, and the plate with the outside of the apparatus. Vent holes may be provided. According to this configuration, it is possible to prevent the space surrounded by the magnetic fluid, the voice coil, the magnet, and the yoke from being sealed.

Further, for example, the shape of the voice coil viewed in the coil axis direction is a circle, a track shape, a rectangle, a rectangle with rounded corners, an ellipse, and a shape in which a plurality of linear portions are connected by a continuous curved portion, It may have any one shape. According to this configuration, speakers having various shapes can be realized.

Further, for example, the shape of the through hole seen in the vibration direction of the diaphragm may be a round shape or a long hole shape. According to this configuration, the distribution of magnetic flux supplied from the magnetic circuit can be adjusted by utilizing the shape of the through hole in accordance with the shape of the voice coil.

FIG. 1A is a top view and a structural cross-sectional view of a first speaker device according to the present disclosure. In FIG. 1A, 1 is a plate, 2a and 2b are magnets (hereinafter, the magnets may be described without being distinguished from each other for convenience, and in this case, the symbol “2” is used for convenience), 3 is a yoke, and 4 is a diaphragm 5 is a plurality of edges, 6 is a voice coil, 7 is a magnetic fluid, and 8 is a frame. A magnetic circuit is formed by the plate 1, the

magnets

2a and 2b, and the yoke 3, and a magnetic gap is formed between the plate 1 and the yoke 3, and the voice coil 6 is disposed in the magnetic gap. Here, an internal magnet type magnetic circuit in which the

magnets

2a and 2b are located inside the voice coil 6 is shown. The

magnets

2a and 2b and the yoke 3 are coupled by being fixed to each other by bonding or the like, and the

magnets

2a and 2b and the plate 1 are coupled to each other by being fixed to each other by bonding or the like. The voice coil 6 is fixed to the diaphragm 4, and the diaphragm 4 is supported by a plurality of edges 5 at the outer periphery, and the edge 5 is fixed to the frame 8. Further, the frame 8 is fixed to the outer surface of the yoke 3 to hold the magnetic circuit.

The magnetic circuit has a through-hole T penetrating in the vibration direction of the diaphragm 4 inside the voice coil 6. Here, the

magnets

2a and 2b are arranged side by side so that each of them forms a semi-annular shape as viewed in the vibration direction and are combined in an annular shape, thereby forming a direct-current magnetic flux generation source as a whole, Surrounds T. Further, here, the through hole T passes through the plate 1 and the yoke 3. Although any shape is possible as the shape of the through-hole T as viewed in the vibration direction of the diaphragm 4, the shape is round here, particularly circular. In addition to this, the round shape includes an ellipse, a shape surrounded by a closed curve having no symmetry in the spread, a rounded polygon, and the like. By forming the through hole T in a round shape, magnetic flux with improved distribution uniformity can be supplied from the magnetic circuit to the voice coil 6 having a round shape when viewed in the coil axial direction, such as a circular coil. it can.

Hereinafter, the operation of this speaker device will be described. When a sound signal is applied to the voice coil 6, a force proportional to the magnetic flux density in the magnetic gap and the flowing current is generated in the voice coil in accordance with the Fleming left-hand rule. As a result, the diaphragm 4 vibrates and reproduces sound. Unlike a general electrodynamic speaker, the edge 5 is a divided edge divided into a plurality of parts, and therefore does not have a role of separating the space before and after the diaphragm 4. However, since the magnetic fluid 7 is filled outside the voice coil 6, the space on the back side of the diaphragm and the space on the front side of the diaphragm are separated. For this reason, the sound reproduced from the front surface of the diaphragm is not canceled out by the antiphase sound generated from the rear surface of the diaphragm inside the voice coil. Further, since the edge 5 is a divided edge, the stiffness of the support can be reduced, and even if the speaker is downsized, it can be operated with a large amplitude.

Generally, since magnets are manufactured by sintering, shrinkage occurs during sintering. For this reason, it is difficult to obtain the accuracy of the shape of the magnet. Moreover, when a magnetic circuit is comprised with several magnets like the

magnets

2a and 2b, possibility that a clearance gap will arise between magnets is very high. FIG. 1A shows a gap g that is a boundary region between the

magnets

2a and 2b. Further, as shown in FIG. 1A, the magnetic fluid 7 is disposed only on the outer peripheral side of the voice coil 6, that is, only on the yoke 3 side of the yoke 3 side and the plate 1 side of the voice coil. The magnetic fluid 7 is not arranged on the plate 1 side. As a result, it is possible to prevent the magnetic fluid 7 from being sucked into the gap between the magnets due to a capillary phenomenon, which occurs when it is assumed that the magnetic fluid 7 is disposed inside the voice coil 6. If the magnetic fluid 7 is sucked into the gap between the magnets, the magnetic fluid 7 in the magnetic gap is reduced, and as a result, the space around the diaphragm 4 may be connected. When the spaces before and after the diaphragm 4 are connected, the sounds generated from the spaces before and after the diaphragm 4 cancel each other, particularly leading to a decrease in sound pressure on the bass side. Therefore, by disposing the magnetic fluid 7 only on the outside of the voice coil 6, the magnetic fluid 7 can be prevented from moving into the gap. In FIG. 1A, the magnet is divided into two, but the number of divisions may be arbitrary. In the case of two divisions, if the

magnets

2a and 2b have the same shape, they can be handled as the same member, which is advantageous in terms of manufacturing cost, material procurement, etc. 2a and 2b may have different shapes. Although an example in which the magnet is divided into two parts is given here, the number of divisions may be any number of two or more.

FIG. 1B is a top view and a cross-sectional view of a first speaker device according to another configuration. The speaker device of FIG. 1B includes constituent members that can be referred to by the names of the constituent members corresponding to reference numerals 1 to 8 described with reference to FIG. 1A. However, differences from the speaker device of FIG. In the speaker device of FIG. 1B, the magnetic fluid 7 is disposed on the outer peripheral side of the voice coil 6, that is, on the yoke 3 side of the voice coil 6, and on the inner peripheral side of the voice coil 6, that is, on the plate 1 side. A magnetic fluid 7b is provided. The magnetic fluid 7a and the magnetic fluid 7b may be of the same type or different types. Further, in order to prevent the space V surrounded by the magnetic fluid 7, the voice coil 6, the magnet 2a, and the yoke 3 from being sealed, for example, at the bottom of the yoke 3, the air hole 3a that communicates the space V with the outside of the speaker device. Any number may be provided.

FIG. 1C is a top view and a cross-sectional view of a first speaker device according to still another configuration. The speaker device of FIG. 1C includes constituent members that can be referred to by the names of the constituent members corresponding to reference numerals 1 to 8 described with reference to FIG. The edge 5 in FIG. 1C is provided along the entire circumference of the speaker device unlike the divided edge like the edge 5 in FIG. 1A and separates the space before and after the diaphragm 4. In this way, a magnetic circuit configured using a plurality of magnets may be combined with edges provided along the entire circumference of the speaker device. Also in this configuration, the magnetic fluid 7 can be prevented from being sucked into the gap between the magnets by a capillary phenomenon by disposing the magnetic fluid 7 only on the outer peripheral side of the voice coil 6, that is, only on the yoke 3 side. It should be noted that the edge provided along the entire circumference of the speaker device can be applied to a speaker device having a configuration described elsewhere.

The speaker device shown in FIGS. 1A to 1C is an internal magnetic circuit, but FIG. 2 shows a cross-sectional view of the structure of the speaker device which is an external magnetic circuit. The speaker device of FIG. 2 includes constituent members that can be referred to by the names of the constituent members corresponding to reference numerals 1 to 8 described with reference to FIG. 1A. However, differences from the speaker device of FIG. Since the speaker device shown in FIG. 2 is an external magnetic type magnetic circuit, the

magnets

2 a and 2 b are located outside the voice coil 6. The frame 8 is fixed to the upper surface of the plate 1. Unlike the case of the internal magnet type magnetic circuit, the magnetic fluid 7 is located inside the voice coil 6, but since it is arranged on the yoke side of the voice coil 6 as in the case of the internal magnet type magnetic circuit, a plurality of magnets are provided. There is no contact between the gaps. For this reason, the magnetic fluid 7 is not sucked into the gaps between the plurality of magnets, and a stable operation can be realized. In FIG. 2, the magnet is divided into two parts, but the number of divisions may be any number of two or more. In the case of two divisions, if the

magnets

2a and 2b have the same shape, they can be handled as the same member, which is advantageous in terms of manufacturing cost, material procurement, etc. 2a and 2b may have different shapes.

FIG. 3 is a top view and a structural cross-sectional view of a second speaker device according to the present disclosure. The speaker device of FIG. 3 includes constituent members that can be referred to by the names of the constituent members corresponding to reference numerals 1 to 8 described for the first speaker device, but the points that are particularly different from the first speaker device will be described. The speaker device of FIG. 3 includes a sealing unit 9 disposed between the plurality of

magnets

2a and 2b. The sealing means 9 is composed of a filling member that fills a gap g between the

magnets

2a and 2b. Specifically, an adhesive or a resin may be used as the material for the sealing means 9. Further, the position of the magnetic fluid 7 in the second speaker device is different from that of the first speaker device, and the magnetic fluid 7 is provided inside the voice coil 6, that is, on the plate 1 side. The operation of the speaker and the effect of sealing the space around the diaphragm 4 of the magnetic fluid 7 are omitted because the principle of the magnetic fluid is the same as that of the first speaker device, although the position of the magnetic fluid is different. The sealing means 9 fills the gap g between the

magnets

2a and 2b, eliminates the gap between the magnets, prevents the space before and after the diaphragm 4 from being connected, and the magnetic fluid 7 causes the gap between the magnets by capillary action. Intrusion can be prevented. For this reason, the speaker device can operate with stable performance. The magnetic fluid 7 may be further arranged outside the voice coil 6, that is, on the yoke 3 side.

FIG. 4A is a structural cross-sectional view of a third speaker device according to the present disclosure. The speaker device of FIG. 4A includes constituent members that can be referred to by the names of the constituent members corresponding to reference numerals 1 to 8 described for the first speaker device, and points that are particularly different from the first speaker device will be described. In addition, illustration is abbreviate | omitted about the top view of FIG. 4A corresponding to the top view of a 1st speaker apparatus. The third speaker device is different from the first speaker device in the position of the magnetic fluid 7, and the magnetic fluid 7 is provided inside the voice coil 6, that is, on the plate 1 side. However, the operation of the speaker and the sealing effect of the space around the diaphragm 4 of the magnetic fluid 7 are omitted because the principle is the same as that of the first speaker device although the position of the magnetic fluid 7 is different. In addition, the third speaker device includes a sealing unit 91. The sealing means 91 is made of a cylindrical nonmagnetic material, and is disposed inside the

magnets

2a and 2b to form a cover member that covers the inner peripheral side of the DC magnetic flux generation source. The cover member only needs to cover at least the boundary region between the

magnets

2a and 2b from the inside of the

magnets

2a and 2b, and is not necessarily cylindrical, and may be provided for each boundary region. Since the gap between the

magnets

2a and 2b and the central through hole T can be separated by the sealing means 91, the space before and after the diaphragm 4 is connected, and the sound around the diaphragm 4 is canceled. Can be prevented. The sealing means 91 may not be completely airtight in preventing the communication between the spaces, and any nonmagnetic material such as resin, ceramic, metal, inorganic film can be applied to the cover member. The magnetic fluid 7 may also be provided outside the voice coil 6, that is, on the yoke 3 side.

The sealing means 91 is arranged only inside the

magnets

2a and 2b. However, as shown in FIG. 3, the sealing means 91 may be used in combination with a type in which the sealing means 9 is filled in the gap between the

magnets

2a and 2b. good. In this case, in addition to the effect when only the sealing means 91 is used as the sealing means, the movement of the magnetic fluid 7 to the gap due to the capillary phenomenon can be prevented. Further, since the sealing means 91 passes through the inside of the

magnets

2a and 2b and penetrates the plate 1 and the yoke 3, it can be used as a positioning jig at the time of manufacture.

FIG. 4B is a structural cross-sectional view of a third speaker device according to another configuration. In the speaker device of FIG. 4B, points that are particularly different from the speaker device of FIG. 4A will be described. The speaker device shown in FIG. 4B includes a sealing unit 92. The sealing means 92 is different from the sealing means 91 shown in FIG. 4A in the position provided in the speaker device, and is arranged outside the

magnets

2a and 2b to cover the outer peripheral side of the DC magnetic flux generation source. I am doing. The cover member only needs to cover at least the boundary region between the

magnets

2a and 2b from the outside of the

magnets

2a and 2b, and may be cylindrical or may be provided for each boundary region. In this case, the sealing means 92 separates the outside of the

magnets

2a and 2b from the gap between the

magnets

2a and 2b and the central through hole T. With this configuration, it is possible to prevent the spaces before and after the diaphragm 4 from being connected and canceling out the sound around the diaphragm 4. Further, in this case, it may be used together with a configuration in which the gap between the

magnets

2a and 2b is filled with the sealing means 9 as shown in FIG. 3, but it is sealed outside the

magnets

2a and 2b as shown in FIG. 4B. Even if it only stops, there exists an effect which prevents the movement to the said clearance gap by the capillary phenomenon of the magnetic fluid 7. FIG.

Also, a speaker device including both the sealing means 91 of FIG. 4A and the sealing means 92 of FIG. 4B can be configured.

FIG. 5 is a structural cross-sectional view of the fourth speaker device according to the present disclosure. The speaker device of FIG. 5 includes constituent members that can be referred to by the names of the constituent members corresponding to reference numerals 1 to 8 described for the first speaker device, but the points that are particularly different from the first speaker device will be described. Note that the top view of FIG. 5 corresponding to the top view of the first speaker device is not shown. The position of the magnetic fluid 7 is different from that of the first speaker device in the fourth speaker device, and the magnetic fluid 7 is provided inside the voice coil 6, that is, on the plate 1 side. However, the operation of the speaker and the sealing effect of the space around the diaphragm 4 of the magnetic fluid 7 are omitted because the principle is the same as that of the first speaker device although the position of the magnetic fluid 7 is different. The fourth speaker device includes a sealing unit 93. The sealing means 93 is formed of a cylindrical nonmagnetic material and is disposed inside the

magnets

2a and 2b from the inside of the

magnets

2a and 2b, and is not necessarily cylindrical, and may be provided for each boundary region. By separating the gap between the

magnets

2a and 2b and the central through hole T by the sealing means 93, the space before and after the diaphragm 4 is connected, and the cancellation of the sound before and after the diaphragm is prevented. Yes. Unlike the third speaker device, the sealing means 93 is provided with an overhanging portion 93a that protrudes on the lower surface of the yoke 3 that is a magnetic circuit constituent member surface surrounding one through end of the through hole T. It is also possible to use the sealing means 93 as a jig that can easily position the member during manufacturing. For this reason, it becomes possible to separate the space around the diaphragm 4 with higher accuracy.

The sealing means 93 is disposed only inside the

magnets

2a and 2b. However, as shown in FIG. 3, the sealing means 93 may be used in combination with a type in which the sealing means 9 is filled in the gap between the

magnets

2a and 2b. good. In this case, in addition to the effect when only the sealing means 91 is used as the sealing means, the movement of the magnetic fluid 7 to the gap due to the capillary phenomenon can be prevented. Further, the projecting portion 93a may be provided so as to project on the upper surface of the plate 1 which is the surface of the magnetic circuit constituting member surrounding the penetrating end of the through hole T on the plate 1 side. The overhanging portion 93a may be provided on both of the upper surface of 1.

FIG. 6A is a top view and a cross-sectional view of a fifth speaker device according to the present disclosure. The speaker device of FIG. 6A includes constituent members that can be referred to by the names of the constituent members corresponding to reference numerals 1 to 8 and 91 described for the speaker device of FIG. 4A, but the points that are particularly different from the speaker device of FIG. 4A will be described. . As shown in FIG. 6A, the shapes of the diaphragm 4 and the voice coil 6 are two curves connecting two parallel line segments and opposite ends of the line segments as viewed in the coil axis direction. It is a track shape constituted by two symmetrical arcs. Along with this, the diaphragm 4 has a shape covering the area surrounded by the track-shaped voice coil 6, and the edges 5 provided so as to support the diaphragm 4 on the both end sides of the track are the frames 7. It is fixed to. The plate surface of the diaphragm 4 is a region surrounded by the voice coil 6 when viewed in the coil axis direction in a region in which the concave and convex shapes are periodically repeated along the direction connecting the edges 5 facing each other across the diaphragm 4. It has a similar shape. The frame 7 holds the outer surface of the yoke 3 on both ends of the track. When the track shape is elongated along the parallel line segments as shown in FIG. 6A, the speaker device is provided with such an elongated shape, thereby improving the degree of freedom of installation of the speaker device. Since operations and effects are the same as those of the fourth speaker device, description thereof will be omitted.

In the speaker device of FIG. 6A, a plurality (three in this case) of through holes T are provided inside the voice coil 6. The sealing means 91 having the material and shape described in FIG. 4A is disposed outside each through hole T. Here, a plurality of through holes T are arranged in a line in the direction of the line segment, and the

magnets

2a and 2b provided on the inner side of the voice coil 6 connect each through hole T from both sides of the line. It is arranged so as to be sandwiched. The sealing means 91 is in a state in which a gap g formed in the boundary region between the

magnets

2a and 2b along the center of the row is covered from the region side of the through hole T that is inside the

magnets

2a and 2b. Further, the plate 1 is provided in a shape surrounded by the voice coil 6, and the yoke 3 is provided so as to cross the region immediately below the region surrounded by the voice coil 6 in four directions. Each through hole T passes through the plate 1 and the yoke 3, and the sealing means 91 covers the entire perimeter of the through region of the through hole T. When a plurality of through holes T are arranged, the asymmetric distribution of the magnetic flux supplied from the magnetic circuit, which occurs when using the voice coil 6 having an elongated shape when viewed in the coil axis direction, is caused by the arrangement of the through holes T. Can be improved.

FIG. 6B is a top view and a cross-sectional view of a fifth speaker device according to another configuration. The difference between the speaker device of FIG. 6B and the speaker device of FIG. 6A will be described. In the speaker device of FIG. 6B, the through hole T has a long hole shape when viewed in the coil axis direction. The slot has a longitudinal direction along parallel lines of the track. The

magnets

2a and 2b are arranged so as to sandwich the through hole T from both sides of the row. The sealing means 91 is in a state in which a gap g formed in the boundary region between the

magnets

2a and 2b along the longitudinal direction of the through hole T is covered from the region side of the through hole T that is inside the

magnets

2a and 2b. . In this way, when the through hole T is formed in the shape of an elongated hole, when the speaker device is installed in an elongated shape, when a plurality of the through holes T are arranged, the voice having an elongated shape when viewed in the coil axis direction. The asymmetric distribution of the supplied magnetic flux from the magnetic circuit, which occurs when the coil 6 is used, can be improved by the long hole-shaped through hole T. In addition, it is easy to form a through-hole because the shape of each magnet is complicated, non-uniform, and does not require excessive processing in order to form a through-hole having an effective size in a combined structure of a plurality of magnets. A plurality of elongated hole-shaped through holes T may be provided as described with reference to FIG. 6A.

FIG. 6C is a top view and a structural cross-sectional view of a fifth speaker device according to still another configuration. The difference between the speaker device of FIG. 6C and the speaker device of FIG. 6A will be described. Note that the top view of FIG. 6C corresponding to the top view of FIG. 6A is omitted. The speaker device in FIG. 6C includes a voice coil 6 that is rectangular when viewed in the coil axis direction. Here, the voice coil 6 has a shape in which curves, so-called fillets are provided at four corners of a rectangle, or a shape in which two sets of parallel line segments are connected by a curve. In general, it has a rectangular shape with rounded corners. The inner diameter of the curved portion (R portion) of the voice coil 6 is preferably 0.5 mm or more so that the magnetic fluid 7 does not crawl up to the diaphragm 4 side at the R portion (rounded corner) due to capillary action. Accordingly, the diaphragm 4 has a shape that covers the region surrounded by the rectangular voice coil 6, and the edge 5 is provided so as to support the diaphragm 4 on a pair of opposing end sides of the rectangle. Is fixed to the frame 7. The plate surface of the diaphragm 4 is a region surrounded by the voice coil 6 when viewed in the coil axis direction in a region in which the concave and convex shapes are periodically repeated along the direction connecting the edges 5 facing each other across the diaphragm 4. It has a similar shape. The frame 7 holds the outer surface of the yoke 3 at both ends of the rectangle. When the track shape is elongated as shown in FIG. 6C, the degree of freedom of installation of the speaker device is improved similarly to the speaker device of FIG. 6A.

Further, the speaker device of FIG. 6C includes

magnets

2 a and 2 b inside the voice coil 6. And the long-hole-shaped through-hole T arrange | positioned so that it may be inserted | pinched between the said

magnets

2a and 2b is formed. A gap g formed in the boundary region between the

magnets

2 a and 2 b is along the longitudinal direction of the through hole T. On the outside of the

magnets

2a and 2b, the sealing means 92 having the material and shape described in FIG. 4B is provided. Further, the plate 1 (not shown) is formed in a shape surrounded by the voice coil 6, and the yoke 3 is provided so as to cross the region immediately below the region surrounded by the voice coil 6 in four directions. Each through hole T passes through the plate 1 and the yoke 3.

In the first to fifth speaker devices described above, the shape of the voice coil 6 viewed in the coil axis direction can be interchanged between a circle, a track shape, a rectangle, and a rectangle with rounded corners. In addition, an ellipse or a shape in which a plurality of straight line portions are joined by a curved portion can be applied.

The above speaker devices can be provided in speaker mounted devices such as video display devices, audio devices, AV devices, mobile phones, smartphones, tablet PCs, operation terminals, mobile information devices, home appliances, and automobiles. Thereby, speakers of various shapes can be realized. Hereinafter, application examples of such a speaker device will be described.

FIG. 7 is a diagram illustrating the mobile information terminal device 201 according to the present disclosure. In FIG. 7, the mobile information terminal device 201 includes a screen 202 and a speaker device 10. The speaker device 10 is any speaker device selected from, for example, the first to fifth speaker devices. The speaker device 10 may be attached to the mobile information terminal device 201 together with a sealed cabinet or a bass reflex cabinet. Further, the cabinet may be attached to the mobile information terminal device 201 as an open type without being attached. In FIG. 7, the speaker devices 10 are arranged at three locations, but any number of speaker devices 10 may be used as long as the number is one or more. If the number of the speaker devices 10 is one, it will be monaural, but if two or more speakers are used, it can be used as a device for sound field control or HRTF.

By mounting the speaker device 10 on a device having a limited mounting volume such as the mobile information terminal device 201, it is possible to stably perform wide-band reproduction even with a limited volume. As for the mounting direction when the speaker device 10 is mounted, the diaphragm may be directed to the sound hole side or the magnetic circuit may be directed to the sound hole side with respect to the sound hole provided in the housing.

FIG. 8 is a diagram illustrating the image display device 203 according to the present disclosure. More specifically, it is a PC or a thin TV. In FIG. 8, the image display device 203 includes a screen 202 and a speaker device 10. The speaker device 10 is any speaker device selected from, for example, the first to fifth speaker devices. The speaker device 10 may be attached to the image display device 203 together with a sealed cabinet or a bass reflex cabinet. Further, the cabinet may be attached to the image display device 203 as it is without being attached. In FIG. 8, the speaker devices 10 are arranged at a total of 16 locations. If one unit is monaural, two units are stereo, and if two or more units are used (for example, arranged as a line array), it can also be used as a device for sound field control or HRTF.

By mounting the speaker device 10 on a device having a limited mounting volume such as the image display device 203, it is possible to stably perform wide-band reproduction even with a limited volume. As for the mounting direction when the speaker device 10 is mounted, the diaphragm may be directed to the sound hole side or the magnetic circuit may be directed to the sound hole side with respect to the sound hole provided in the housing.

FIG. 9 is a mounting diagram of the vehicle-mounted speaker according to the present disclosure. In FIG. 9, the door 204 of the automobile includes the speaker device 10. The speaker device 10 is any speaker device selected from, for example, the first to fifth speaker devices. The speaker device 10 may be attached to the door 204 of the automobile together with the sealed cabinet or the bass reflex cabinet. Further, the cabinet may be attached as it is to the automobile door 204 as an open type without being attached. In FIG. 9, the speaker devices 10 are arranged at three locations, but any number of speaker devices may be used as long as one or more speaker devices are provided. 9 shows an example in which the speaker device 10 is attached to the door 204 of the automobile. However, the speaker apparatus 10 may be attached to any position of the automobile such as a dashboard, pillar, seat, headrest, or ceiling of the automobile. In addition to automobiles, they may be attached to various moving means such as trains, monorails, linear motors, airplanes, and ships.

Conventionally, large-scale speakers have been required for wide-band reproduction, particularly for reproducing low-pitched sounds. In the speaker device using the magnetic fluid of the present disclosure, a speaker capable of reproducing low-frequency sound can be realized even with a small size. Therefore, the same acoustic characteristics as before can be realized with a speaker that is smaller or lighter than the conventional speaker device. As a result, the entire moving means is reduced in size and weight, and the comfort can be improved by increasing the living space, or the fuel efficiency can be improved by reducing the size and weight of the vehicle body. Regarding the mounting direction of the speaker device 10 at the time of mounting, the diaphragm may be directed to the sound hole side or the magnetic circuit may be directed to the sound hole side with respect to the sound hole provided in the housing.

FIG. 10 is a mounting diagram of the inner earphone 205 according to the present disclosure. In FIG. 10, the inner earphone 205 includes an inner earphone cord 206, an ear chip 207, and a speaker device 10. The speaker device 10 is any speaker device selected from, for example, the first to fifth speaker devices.

Conventionally, since a speaker (receiver) used for the inner earphone 205 has a small aperture, it has been difficult to reproduce a rich bass with a high minimum resonance frequency. By mounting the speaker device 10 of the present disclosure on the inner earphone this time, it is possible to provide an inner earphone that can reproduce richer bass than ever before. As for the mounting direction when the speaker device 10 is mounted, the diaphragm may be directed to the sound hole side or the magnetic circuit may be directed to the sound hole side with respect to the sound hole provided in the housing. Further, the eartip 207 of FIG. 10 is a sealed eartip. However, the eartip 207 has an air hole in the ear tip umbrella portion, and an open type in which outside air can flow from the inside of the ear hole through the air hole of the ear tip. Ear tips may be used. If an open-type ear tip is used, the ear hole can be prevented from becoming stuffy. Further, the disclosure herein relates to the inner earphone 205 provided with the speaker device 10, but the speaker device 10 may be applied to a headset, a headphone, or a hearing aid.

The speaker device according to the present disclosure is small and has a capability of reproducing a wide band and can operate stably, so that it is useful alone as a small high-quality sound speaker. Moreover, in each apparatus which mounts a speaker, it is useful as a small high quality sound quality device.

1, 112

plate

2a, 2b, 111

magnet

3, 110 yoke 3a vent hole 4 diaphragm 5 edge (divided edge)
6, 116

Voice coil

7, 117

Magnetic fluid

8, 115

Frame

9, 91, 92, 93 Sealing means 93a Overhang portion 10 Speaker device 114 Edge 201 Mobile information terminal device 202 Screen 203 Image display device 204 Automotive door 205 Inner earphone 206 Inner earphone code 207 Ear tip
g Clearance T, U Through hole V space

Claims

A magnetic circuit having a magnetic gap;
A voice coil at least partially disposed in the magnetic gap;
A diaphragm to which the voice coil is fixed;
A plurality of supports for supporting the diaphragm;
It is composed of a magnetic fluid disposed on at least one of the voice coil inner periphery and the outer periphery,
The magnetic circuit is configured to include at least a plurality of magnets, a yoke, and a plate, and the magnetic circuit has a through-hole penetrating in the vibration direction of the diaphragm inside the voice coil. Speaker device.
The speaker device according to claim 1, wherein the magnetic fluid is disposed only on a yoke side of the voice coil.
The magnetic fluid is disposed at least on the plate side of the voice coil,
The magnetic circuit is configured to include at least a yoke, a plate, the plurality of magnets, and a filling member filling a boundary region between the plurality of magnets. Item 2. The speaker device according to Item 1.
The magnetic fluid is disposed at least on the plate side of the voice coil,
The first magnetic circuit covers at least a yoke, a plate, the plurality of magnets arranged outside the through-hole, and at least a boundary region between the plurality of magnets from the inside of the plurality of magnets. The speaker device according to claim 1, wherein the speaker device is configured to include a cover member.
5. The speaker device according to claim 4, wherein the first cover member has an overhanging portion protruding on a surface of a magnetic circuit component member surrounding one or both through ends of the through hole. .
The magnetic fluid is disposed at least on the plate side of the voice coil,
The magnetic circuit includes at least a yoke, a plate, the plurality of magnets arranged outside the through hole, and a boundary region between the plurality of magnets from the outside of the plurality of magnets. The speaker device according to claim 1, wherein the speaker device is configured to include a cover member.
The magnetic fluid is disposed on both the yoke side and the plate side of the voice coil,
2. The speaker device according to claim 1, further comprising a vent hole that communicates a space surrounded by the magnetic fluid, the voice coil, the yoke, and the plate with the outside of the device.
The shape seen in the coil axis direction of the voice coil is
2. The device according to claim 1, wherein the shape has any one of a circle, a track shape, a rectangle, a rectangle with rounded corners, an ellipse, and a shape in which a plurality of straight line portions are connected by a continuous curved portion. The speaker device according to 1.
The speaker device according to claim 1, wherein the shape of the through hole seen in the vibration direction of the diaphragm is a round shape or a long hole shape.
In the magnetic circuit, the plurality of magnets and the yoke are fixed to each other, the plurality of magnets and the plate are fixed to each other, and the magnetic gap is provided between the yoke and the plate. The speaker device according to claim 1, wherein the speaker device is provided.
An image display device, an audio device, an AV device, a mobile phone, a smartphone, a tablet PC, an operation terminal, a mobile information device, a home appliance, and an automobile having the speaker device according to any one of claims 1 to 10. A speaker mounting device comprising any one of them.