JP4452656B2 - Speaker device - Google Patents

Description

  The present invention relates to a speaker device.

FIG. 1 shows a configuration of a speaker device proposed by the applicant of the present invention in Patent Document 1 below.
The speaker device 1 includes a diaphragm 3 and a drive cone that is disposed behind the diaphragm 3 coaxially with the diaphragm 3 and whose inner peripheral portion is hermetically joined and integrated with the inner peripheral portion of the diaphragm 3. 5 and diaphragm support portions 7a and 7b for supporting the diaphragm 3 and the outer periphery of the drive cone 5 are provided on the front end side, and the frame 7 on which the magnetic circuit 9 is provided on the central axis of the rear end. And a voice coil 13 wound around a voice coil bobbin 11 integrally joined to the inner periphery of the diaphragm 3 and the drive cone 5 and inserted through the magnetic gap 9 a of the magnetic circuit 9.

  The outer peripheral part of the diaphragm 3 is fixed to the diaphragm supporting part 7a via an edge damper 15 joined to the outer peripheral part. The outer peripheral portion of the drive cone 5 is fixed to the diaphragm support portion 7b via an edge damper 17 joined to the outer peripheral portion.

  The diaphragm support portion 7b is a step set at a position that is appropriately separated from the diaphragm support portion 7a in the axial direction by an appropriate distance. A space between the diaphragm support 7a and the diaphragm support 7b of the frame 7 is a sealed cylindrical wall in which no opening is provided. The cylindrical wall 7 c of the frame 7 closes an opening of a space 19 sandwiched between the diaphragm 3 and the drive cone 5 to form a sealed space, and includes a voice coil 13 due to the spring property of the gas enclosed in the sealed space 19. The vibration system is supported floating.

The magnetic circuit 9 includes a yoke 21 having a structure in which a cylindrical center pole 21b projects from the center of a disk-shaped plate 21a, a ring-shaped magnet 23 that is loosely fitted on the outer periphery of the center pole 21b, and a plate 21a. A ring-shaped top plate 25 is provided so as to be loosely fitted to the front end side of the center pole 21b so as to sandwich the magnet 23 therebetween. A gap between the inner periphery of the top plate 25 and the center pole 21b is a magnetic gap 9a in which the voice coil 13 is disposed.
The magnet 23 has a ring shape concentric with the central axis of the diaphragm 3 and the drive cone 5, and the ring portion has a rectangular cross-sectional shape.

The frame 7 has a shallow bowl shape, and the magnetic circuit 9 is attached to the inner surface of the bottom plate portion 7d with the plate 21a of the yoke 21 mounted thereon. That is, the magnetic circuit 9 is disposed between the rear end portion (bottom plate portion 7 d) of the frame 7 and the drive cone 5.
Between the bottom plate portion 7d of the frame 7 and the diaphragm support portion 7b, an opening 7f as a vent hole for releasing the back pressure of the diaphragm is appropriately provided. The back surface of the diaphragm support portion 7a of the frame 7 functions as a flange surface that is tightly fixed to the baffle of the speaker cabinet.

The above speaker device 1 is manufactured by the following procedure.
First, the magnetic circuit 9 is attached to the rear part of the frame 7, and the voice coil 13 is temporarily assembled. Thereafter, the drive cone 5 is fixed to the diaphragm support 7b, and then the diaphragm 3 is assembled and fixed to the diaphragm support 7a. The inner peripheral portion of the diaphragm 3 is bonded and fixed to the inner peripheral portion of the drive cone 5 to form a sealed space 19. The voice coil bobbin 11 is bonded and fixed to the inner periphery of the drive cone 5.
When the formation of the sealed space 19 is completed, it is inspected whether the sealed property of the sealed space 19 and the characteristics as an air spring are appropriate. If appropriate, a dust cap 27 is attached to the central portion of the diaphragm 3. It will be completed. The dust cap 27 covers the front of the voice coil bobbin 11 and prevents entry of dust and the like into the magnetic gap 9a.

In such a speaker device 1, the spring characteristic as an air spring in the sealed space 19 between the diaphragm 3 and the drive cone 5 controls the vibration of the voice coil bobbin 11, voice coil 13, diaphragm 3 and drive cone 5. Therefore, it is not necessary to provide a dedicated damper for control.
Therefore, the axial dimension of the speaker device 1 can be shortened by omitting the dedicated damper and its installation space, and in particular, the speaker device that is required in the in-vehicle audio system can be thinned.

  In addition, since the drive cone 5 can use the same material as that of the diaphragm 3, the mass is lighter and mechanical fatigue is less likely to occur compared to a conventional bellows structure damper. This can prevent the deterioration of the vibration damping performance and extend the service life of the speaker device. In addition, since there is no significant local deformation, there is no occurrence of singular vibration or rubbing noise that causes the sound quality to become turbid. High-quality sound reproduction without noise can be realized.

Japanese Patent Application No. 2003-428374

Incidentally, in order to increase the driving force of the diaphragm 3 and the drive cone 5 and further improve the speaker performance, it is effective to increase the magnetic flux density of the magnetic gap 9a.
And in order to raise the magnetic flux density of the magnetic clearance gap 9a, enlarging the magnet 23 can be considered.

On the other hand, in the speaker device 1 described above, the arrangement of the magnet 23 must be set so that the drive cone 5 does not interfere with the corner portion 23a of the magnet 23 when the drive cone 5 is displaced rearward.
That is, the size of the magnet 23 must be set so that the corner portion 23a is positioned at a position that is appropriately retracted from the maximum displacement position E1 to the rear of the drive cone 5 by the separation distance s1. By restricting the position of the portion 23a, the outer diameter dimension D1 is determined. Even if an empty space remains on the outer periphery of the magnet 23 as shown in FIG. There was a problem.

Therefore, the speaker device 2 shown in FIG. 2 has been studied.
Since the speaker device 2 shown in FIG. 2 employs a magnet 24 having a pentagonal cross section with a chamfered corner on the drive cone 5 side, the slanted chamfered portion 24a causes the maximum displacement position E1 of the drive cone 5 to be rearward. A separation distance s2 can be secured between them. The separation distance s2 can be secured larger than the separation distance s1 of the rectangular magnet 23 in the speaker device 1 of FIG.
Further, the outer diameter D2 on the rear end side can be made larger by a dimension w2 than the magnet 23 having a rectangular cross section by effectively utilizing the empty space on the rear end side of the frame 7. That is, by increasing the outer diameter, the magnetic flux density of the magnetic gap 9a can be increased and the speaker performance can be improved.

However, the magnet 24 having the pentagonal cross section as described above has a problem in that it has a special shape, resulting in a significant increase in cost.
Further, if there is a change in the shape of the drive cone 5, etc., a new magnet 24 in which the inclination angle of the chamfered portion 24a has to be changed must be recreated.

  As a problem to be solved by the present invention, a speaker device having a configuration in which a space sandwiched between a diaphragm arranged coaxially and a drive cone is a sealed space, and the voice coil is floatingly supported by the spring property of the gas enclosed in the sealed space. Therefore, the speaker performance can be improved by increasing the outer diameter of the magnet of the magnetic circuit without incurring an increase in cost, and the outer shape of the magnet can be changed without changing the shape of the drive cone. Providing speaker devices that can easily cope with the above is an example.

  The speaker device according to claim 1 includes a diaphragm, a drive cone that is disposed behind the diaphragm coaxially with the diaphragm, and an inner peripheral portion is joined and integrated with an inner peripheral portion of the diaphragm. A diaphragm supporting portion that supports the diaphragm and the outer periphery of the drive cone is disposed on the front end side, and is disposed between the rear end portion of the frame and the drive cone to drive the diaphragm. A magnetic circuit; and a voice coil wound around a voice coil bobbin integrally joined to the diaphragm and the inner periphery of the drive cone, and inserted into a magnetic gap of the magnetic circuit, and the diaphragm and the drive A speaker device in which a space sandwiched between cones is formed in a sealed space, and a vibration system including a voice coil is floated and supported by the spring property of the gas enclosed in the sealed space. The shaped magnet is formed by laminating a plurality of unit magnets, and at least two or more types of unit magnets having different outer diameters are used for the plurality of unit magnets. An outer shape corresponding to the shape of the accommodation space between the drive cone and the drive cone is provided.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of a speaker device according to the invention will be described in detail with reference to the drawings.
FIG. 3 is a longitudinal sectional view showing the configuration of the embodiment of the speaker device according to the present invention.

  The speaker device 31 of this embodiment is arranged integrally with the diaphragm 3 and behind the diaphragm 3 coaxially with the diaphragm 3 and the inner peripheral portion thereof is airtightly joined to the inner peripheral portion of the diaphragm 3. The drive cone 5 and the diaphragm support portion 33a for supporting the diaphragm 3 and the outer periphery of the drive cone 5 are provided on the front end side, and the magnetic circuit 41 is provided on the center axis of the rear end. A frame 33; and a voice coil 13 wound around a voice coil bobbin 11 integrally joined to the inner periphery of the diaphragm 3 and the drive cone 5 and inserted into the magnetic gap 41a of the magnetic circuit 41. 3 and the drive cone 5 are formed in a sealed space 19, and the vibration system including the voice coil 13 is floated and supported by the spring property of the gas enclosed in the sealed space 19.

  However, in the speaker device 31 of the present embodiment, the outer peripheral portion of the drive cone 5 is airtightly fixed to a bracket 35 formed of a metal plate, and is fixed to the frame 33 via the bracket 35.

  The bracket 35 includes a cylindrical wall portion 35a that is inserted inside the diaphragm support portion 33a on the frame 33, and extends radially outward from one end of the cylindrical wall portion 35a to extend the diaphragm support portion of the frame 33. A frame fixing portion 35b fixed to 33a, a first support portion 35c which is mounted on one end side of the cylindrical wall portion 35a and whose outer peripheral portion of the diaphragm 3 is fixed in an airtight manner via the edge damper 15, and a cylindrical wall And a second support portion 35d that is mounted on the other end side of the portion 35a and in which the outer peripheral portion of the drive cone 5 is airtightly fixed via the edge damper 17.

The frame fixing portion 35b is a flange portion extending radially outward from one end of the cylindrical wall portion 35a, and the surface of the frame fixing portion 35b serves as a first support portion 35c.
The cylindrical wall portion 35a of the bracket 35 defines a space sandwiched between the diaphragm 3 and the drive cone 5 in the sealed space 19, and the outer peripheral portion of the diaphragm 3 and the drive cone 5 is a frame fixing portion of the bracket 35. The frame 35b is fixed to the diaphragm 33 by fixing it to the diaphragm support portion 33a.

The frame 33 has a shallow bowl shape, and the magnetic circuit 41 is attached to the inner surface of the rear end wall 33b with the plate 21a of the yoke 21 mounted thereon. That is, the magnetic circuit 41 is disposed between the rear end portion of the frame 33 and the drive cone 5.
Between the rear end wall 33b of the frame 33 and the diaphragm support portion 33a, an opening 33d is appropriately provided as a vent hole for releasing the back pressure of the diaphragm. The back surface of the diaphragm support portion 33a of the frame 33 functions as a flange surface that is tightly fixed to the baffle of the speaker cabinet.

The magnetic circuit 41 fixed to the rear end wall (bottom plate portion) 33b of the frame 33 includes a yoke 21 having a structure in which a cylindrical center pole 21b projects from the center of a disk-shaped plate 21a, and a center pole 21b. A substantially ring-shaped magnet 43 loosely fitted on the outer periphery, and a ring-shaped top plate 25 that is loosely fitted to the front end side of the center pole 21b so as to sandwich the magnet 43 between the plate 21a. Yes.
A gap between the inner periphery of the top plate 25 and the center pole 21b is a magnetic gap 41a in which the voice coil 13 is disposed.

In the case of this embodiment, the magnet 43 is formed by laminating three substantially ring-shaped unit magnets 45, 46, 47.
The three unit magnets 45, 46, and 47 have the same inner diameter, but have different outer diameters so that the outer diameters become smaller in order from the plate 21a side toward the drive cone 5 side. Are arranged in a stack.
The outer diameter D3 of the unit magnet 45 having the maximum outer diameter that is laminated on the plate 21a is set as large as possible within the range allowed by the space on the rear end side of the frame 33. The outer diameter of the uppermost unit magnet 47 positioned on the drive cone 5 side is set such that a sufficient separation distance s3 from the maximum displacement position E1 to the rear of the drive cone 5 can be secured. Has been.
This separation distance s3 can be ensured to be greater than the separation distance s1 of one rectangular magnet 23 in the speaker device 1 of FIG.
The magnet 43 has a substantially pentagonal outer shape corresponding to the accommodation space shape between the frame 33 and the drive cone 5 by stacking the above three unit magnets 45, 46, 47. .

  As shown in FIG. 3, the speaker device 31 of the present embodiment is manufactured by fixing the drive cone 5 to the bracket 35 and vibrating the diaphragm 3 and the drive cone 5 to define a sealed space 19. A plate assembly 37 is formed. Then, the diaphragm assembly 37 is inspected for hermeticity and spring characteristics of the sealed space 19, and if it is confirmed that there is no defect, the diaphragm assembly 37 is assembled with the magnetic circuit 41 or the like. Is assembled to the completed frame 33. When the adhesion between the drive cone 5 and the voice coil bobbin 11 in the sealed space 19 is completed, a dust cap 27 is adhered to the opening at the center of the diaphragm 3 as shown in FIG. Prevent the entry of etc.

  The mutual abutment surfaces of the frame fixing portion 35b and the diaphragm support portion 33a of the bracket 35 are bonded by applying a double-sided adhesive tape, an uncured adhesive, or the like to fix the frame 33 and the bracket 35. ing.

The packing 39 serves as a packing material for attaching the speaker to the cabinet, and also has an appearance viewed from the front. The packing 39 is a substantially C-shape that wraps the butted portion of the frame fixing portion 35b and the diaphragm support portion 33a from the outside. The airtightness of the butt portion is improved in the shape of the shape.
Further, the packing 39 is in close contact with the baffle of the speaker cabinet to improve the sealing property between the baffle and at the same time, blocks unnecessary vibration transmission between the baffle and the speaker unit.

The speaker device 31 described above has a configuration in which a space sandwiched between the diaphragm 3 and the drive cone 5 arranged coaxially is used as a sealed space 19 and the voice coil is supported in a floating manner by the spring property of the gas contained in the sealed space 19. In the speaker device, the magnet 43 of the magnetic circuit 41 disposed on the back of the drive cone 5 is a laminated structure of a plurality of unit magnets 45, 46, 47, and the unit magnet 47 having the smallest outer diameter is provided on the drive cone 5 side. By laminating the arranged structures, an outer shape having a substantially pentagonal cross section equivalent to a shape in which the corner portion on the drive cone 5 side is chamfered can be formed as a whole.
That is, by disposing the unit magnet 47 having a small outer diameter on the drive cone 5 side, it is easy to ensure the separation distance s3 between the drive cone 5 and the rearward maximum displacement position E1. The unit magnet 45 disposed on the rear end side of the frame 33 employs a unit magnet having a larger outer diameter D3 than the conventional rectangular magnet 23 by a dimension w3, thereby freeing space in the frame 33. The magnet can be effectively utilized, and the diameter of the magnet effective for improving the magnetic flux density can be increased.
Moreover, the unit magnets 45, 46, 47 themselves to be stacked do not require chamfering at the corners and may have a ring-shaped structure with a simple rectangular cross section. Does not occur.
Therefore, the speaker performance can be improved by increasing the outer diameter of the magnet 43 of the magnetic circuit 41 without increasing the cost.

  In addition, the outer shape of the magnet 43 can be changed flexibly by changing the number of unit magnets 45, 46, 47 to be stacked as the shape of the drive cone 5 is changed. Therefore, it is possible to easily cope with a change in the specification of the diaphragm without incurring costs.

For explanation, the speaker device 31 according to the present embodiment uses the space between the diaphragm 3 and the drive cone 5 arranged coaxially as a sealed space 19, and the voice due to the spring property of the gas contained in the sealed space 19. Since the speaker device 31 is configured to support the coil 13 in a floating manner, it is not necessary to provide a dedicated damper for controlling the vibration of the voice coil bobbin 11 and the diaphragm 3.
Therefore, the axial dimension of the speaker device 31 can be shortened by omitting a dedicated damper and its installation space, and in particular, the speaker device 31 required for an in-vehicle audio system can be thinned.

  In addition, since the drive cone 5 can use the same material as that of the diaphragm 3, the mass is lighter and mechanical fatigue is less likely to occur compared to a conventional bellows structure damper. Therefore, it is possible to realize a longer service life of the speaker device 31 and to prevent the occurrence of specific vibrations and rubbing noises that cause the sound quality to become cloudy. High-quality sound reproduction without turbidity can also be realized.

  Furthermore, the speaker device 31 of the present embodiment is a diaphragm assembly 37 in which a space sandwiched between the diaphragm 3 and the drive cone 5 is a sealed space 19 by assembling the drive cone 5 to the bracket 35. Prior to installation, the presence or absence of defects in the sealed space 19 can be inspected. If a defect that can be repaired is detected, the repair work can be performed in a small and light state before being attached to the frame 33, so that the sealed space 19 can be easily repaired.

  Even when a defect that cannot be repaired occurs in the sealed space 19, only the diaphragm 3, the drive cone 5, and the bracket 35 can be discarded regardless of many components such as the magnetic circuit 41 incorporated in the frame 33. Therefore, as compared with the configuration shown in FIG. 1 in which the outer peripheral portions of the diaphragm 3 and the drive cone 5 are directly joined and integrated with the frame, the amount of waste can be suppressed and the economic loss can be reduced.

Then, the speaker device 31 of the present embodiment has a manufacturing method in which the diaphragm assembly 37 is made as described above, and then the diaphragm assembly 37 is attached to the frame after the assembly of the magnetic circuit 41 and the like. The manufacturing method of assembling to 33 can be adopted.
In the case of this manufacturing method, the diaphragm support portion 33a provided in the frame 33 is sufficient for fixing the bracket 35 of the diaphragm assembly 37, and it is necessary to equip each diaphragm individually. Absent. That is, by reducing the number of processing portions of the diaphragm support portion 33a on the frame 33, it is possible to reduce the processing cost of the frame 33, which is a large component, and to reduce the cost of the product.

  Moreover, since the installation location of the diaphragm support portion 33a is only one, the dimension between the rear end wall 33b of the frame 33 and the diaphragm support portion 33a is increased, and as a ventilation hole formed in the portion. It is also possible to reduce the weight of the speaker unit by making the opening 33d have a large diameter.

  Further, in the speaker device 31 of the present embodiment, the packing 39 that urges the diaphragm support portion 33a on the frame 33 and the frame fixing portion 35b of the bracket 35 to urge each other is formed of a vibration absorbing material such as rubber. Since the vibration transmission between the frame 33 and the bracket 35 is cut off, unnecessary vibration from the magnetic circuit 41 does not affect the diaphragm, and the acoustic characteristics and reproduction performance can be improved.

  In the above embodiment, the edge damper 15 has the roll portion 15a that allows the amplitude of the diaphragm 3 attached to the front side of the diaphragm in a convex form. In addition, the edge damper 17 has a roll portion 17a that allows the amplitude of the drive cone 5 mounted in a convex shape on the rear side of the diaphragm. Although consideration is given so that the capacity of the sealed space 19 can be ensured to the maximum by setting the direction of each of the roll portions 15a and 17a, if each of the roll portions has a damper characteristic necessary for an air cushion, The directions of 15a and 17a are not limited to the above embodiment. For example, the direction of each of the roll portions 15a and 17a may be set in the opposite direction to the above embodiment.

In the speaker device of the present embodiment, the number of unit magnets constituting the magnet, the outer diameter of each unit magnet, and the like are not limited to those in the above embodiment.
The number of unit magnets stacked can be set to an appropriate number of two or more. Further, it is not necessary that all unit magnets to be laminated have different outer diameters. For example, a part of the unit magnets having the same outer diameter may be stacked.

As described above in detail, the speaker device 31 according to the embodiment of the present invention is arranged behind the diaphragm 3 coaxially with the diaphragm 3, and the inner peripheral portion thereof is the diaphragm 3. A drive cone 5 joined and integrated to the inner peripheral portion, a diaphragm 33 provided on the front end side with a diaphragm supporting portion 33a for supporting the diaphragm 3 and the outer peripheral portion of the drive cone 5, and a rear end portion of the frame 33 Of the magnetic circuit 41 wound around the voice coil bobbin 11 joined and integrated to the inner periphery of the diaphragm 3 and the drive cone 5. The voice coil 13 is inserted into the magnetic gap 41a, and a space sandwiched between the diaphragm 3 and the drive cone 5 is formed in the sealed space 19, and the voice coil 13 is formed by the spring property of the gas enclosed in the sealed space 19. Including In the speaker device in which the vibration system is suspended, the substantially ring-shaped magnet 43 of the magnetic circuit 41 is formed by laminating a plurality of unit magnets 45 to 47 and a plurality of unit magnets 45 to 47. 47 is provided with an outer shape corresponding to the shape of the accommodating space between the frame 33 and the drive cone 5 by using at least two types of unit magnets having different outer diameters.
As described above, the magnet 43 of the magnetic circuit 41 arranged on the back of the drive cone 5 has a laminated structure of a plurality of unit magnets 45 to 47, and is laminated in a structure in which a unit magnet having a small outer diameter is arranged on the drive cone 5 side. As a result, the outer shape of the pentagonal cross section equivalent to the shape of the chamfered corner portion on the drive cone side can be formed as a whole.
That is, by disposing the unit magnet having a small outer diameter on the drive cone side, it is easy to ensure the separation distance s3 from the maximum displacement position E1 to the rear of the drive cone 5. In addition, by adopting a unit magnet with a large outer diameter for the unit magnet placed on the rear end side of the frame, it is possible to effectively utilize the empty space in the frame, which is effective in improving the magnetic flux density. An increase in diameter of 43 can also be realized.
In addition, the unit magnets to be stacked themselves do not require chamfering at the corners, and may be of a ring-like structure with a simple rectangular cross section. Therefore, the cost does not actually increase due to processing such as chamfering.
Therefore, the speaker performance can be improved by increasing the outer diameter of the magnet 43 of the magnetic circuit 41 without increasing the cost.
In addition, the outer shape change of the magnet 43 accompanying the change in the shape of the drive cone 5 can be flexibly handled by changing the number of unit magnets to be stacked, etc., thereby avoiding new production of unit magnets having different shapes. Therefore, it is possible to easily cope with a change in the specification of the diaphragm without cost.

  The drive cone 5 is not limited to the shape of the above embodiment, and may be any shape as long as it transmits the drive of the voice coil 13 to the diaphragm 3.

It is a longitudinal cross-sectional view which shows the structure of the speaker apparatus which the present applicant previously proposed. It is a longitudinal cross-sectional view of the improvement proposal of the speaker apparatus of FIG. It is a longitudinal cross-sectional view which shows the structure of one Embodiment of the speaker apparatus based on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 3 Diaphragm 5 Drive cone 11 Voice coil bobbin 13 Voice coil 15 Edge damper 15a Roll part 17 Edge damper 17a Roll part 19 Sealed space 31 Speaker apparatus 33 Frame 33a Diaphragm support part 33b Rear end wall (bottom plate part)
33d Opening 35 Bracket 35a Cylindrical wall part 35b Frame fixing part 35c First support part 35d Second support part 37 Diaphragm assembly 39 Packing 41 Magnetic circuit 41a Magnetic gap 43 Magnet 45 to 47 Unit magnet

Claims (1)

A diaphragm, a drive cone disposed coaxially with the diaphragm behind the diaphragm and having an inner peripheral portion joined and integrated with an inner peripheral portion of the diaphragm, and outer peripheries of the diaphragm and the drive cone A frame provided with a diaphragm supporting part on the front end side, a magnetic circuit disposed between the rear end part of the frame and the drive cone, and driving the diaphragm, the diaphragm and the drive A voice coil wound around a voice coil bobbin joined and integrated with the inner periphery of the cone and inserted into a magnetic gap of the magnetic circuit, and a space sandwiched between the diaphragm and the drive cone is formed in a sealed space And a speaker device in which a vibration system including a voice coil is supported in a floating manner by the spring property of the gas enclosed in the sealed space,
The substantially ring-shaped magnet of the magnetic circuit is formed by laminating a plurality of unit magnets, and at least two types of unit magnets having different outer diameters are used for the plurality of unit magnets. And a speaker device having an outer shape corresponding to a shape of a housing space between the frame and the drive cone.

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