JPH08251692A - Speaker - Google Patents

Abstract

PURPOSE: To surely fix a member constituting a magnetic circuit in the frame of a speaker through easy work. CONSTITUTION: A fixing member 19 is inserted into a ring-shaped york 17 constituting the magnetic circuit A1 in the frame 11 of the speaker and the tip of the member 19 is projected from a center hole 11e. The member 19 is press-molded by caulking tools 21, 22 from the upper and lower sides of the member 19 and the york 17 is fixed to the frame 11 by the caulking work. Since no metallic powder is generated as in the conventional thread fastening work, no metallic powder sticks to the gaps G1, G2 of the circuit A1. When the member 19 is formed by a non-magnetic metallic member, the member 19 displays also the function of a heat discharging member.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speaker in which a diaphragm, a coil and a magnetic circuit are housed in a frame, and more particularly to a speaker in which the magnetic circuit is securely fixed in the frame.

[0002]

2. Description of the Related Art FIG. 3 (a) is a sectional view showing a conventional dynamic speaker for use in a vehicle, and FIG. 3 (b) is an enlarged sectional view of a magnetic circuit A shown in FIG. 3 (a). FIG.
In the speaker shown in (a), a cone-shaped diaphragm 2 made of paper is provided in the frame 1. The conical bottom portion 2a of the diaphragm 2 is connected to the opening edge portion 1a of the frame 1 via a deforming joint portion 4 having a semi-cylindrical cross section. The outer periphery of the conical head portion 2b of the diaphragm 2 is supported on the inner surface of the frame 1 via a damper 5. The damper 5 is formed of a flexible sheet, a paper material, a resin film, or the like, in which resin fibers are knitted, and has multiple concentric corrugations. The vibrating plate 2 is supported by the deformable joint 4 and the damper 5 in a vibratable state.

A cylindrical bobbin 6 is connected to the conical head 2b of the diaphragm 2, and a pair of coils (voice coils) C1 and C2 are wound around the outer circumference of the bobbin 6. The bobbin 6 is formed of a paper material, a paper material impregnated with a resin, or the like.

A ring-shaped member forming a magnetic circuit A is provided on the base end side of the frame 1. In FIG. 3B, the ring-shaped member provided inside the bobbin 6 is the yoke 7, which is made of a magnetic material having high magnetic permeability. A ring-shaped member provided outside the bobbin 6 is a magnet 8 magnetized so as to have magnetic anisotropy in the axial direction,
A magnetic body 8 of high magnetic permeability connected to both axial end surfaces of the magnet 8.
It is composed of a and 8b.

A pair of gaps G1 and G2 are formed in the facing portion of the yoke 7 and the magnetic bodies 8a and 8b, and the coil C1
And C2 are located within their respective gaps. Magnet 8
The vertical magnetic field in the Y-axis direction generated from the magnetic bodies 8a and 8b
Is converted into a transverse magnetic field toward the gaps G1 and G2 by
A magnetic flux is applied across the coils C1 and C2 located in the gaps G1 and G2. When a voice current is applied to the coils C1 and C2, by this current and the magnetic flux,
Electromagnetic force (driving force) in the Y-axis direction on the coils C1 and C2
Acts on the vibrating plate together with the coils C1 and C2 and the bobbin 6.

[0006]

In the magnetic circuit A of the conventional type of speaker shown in FIGS. 3 (a) and 3 (b), the step 1c on the inner peripheral side and the step on the outer peripheral side are formed on the base end side of the frame 1. 1
d is formed, and the yoke 7, which constitutes the magnetic circuit A, the magnet 8 and the magnetic body 8b are positioned between the steps and are fixed with an adhesive.

However, in the structure in which the members forming the magnetic circuit A are fixed only by the adhesive, the attachment strength is low. That is, due to the alternating voice current flowing through the coils C1 and C2, the coils C1 and C2 generate Joule heat, and this heat is generated by the yoke 7, the magnet 8 and the magnetic bodies 8a, 8a.
b. Due to this heat, the adhesive force of the adhesive that bonds the yoke 7 and the frame 1 or the magnet 8 and the magnetic body 8b and the frame 1 is reduced, and the yoke 7 or the magnet 8 and the magnetic body 8b are attached to the frame 1. There is a drawback that it easily comes off. In particular, if the frame 1 is made of a resin such as ABS in order to reduce the weight of the entire speaker, the heat generated in the coils C1 and C2 and the magnetic circuit A cannot be radiated to the outside, and the heat is accumulated. The influence of heat on the magnetic circuit increases, and the mounting strength of the members forming the magnetic circuit A tends to decrease.

Further, in order to increase the mounting strength of the members constituting the magnetic circuit A, as shown in FIG. 4, a mounting member 9 is provided on the upper portion of the yoke 7, and a screw 10a is mounted on the mounting member 9 on the diaphragm 2 side. From the frame 1 with the tip of the screw 10a
Screw hole 10b at the tip 1e of the convex portion formed at the bottom of the
It is conceivable that the structure is screwed on.

However, in the mounting structure shown in FIG. 4, when the screw head of the screw 10a is tightened and rotated by a screwdriver or the like, iron powder scraped from the male screw portion of the screw 10a or the head of the screw 10a is removed from the yoke 7. There is a risk of passing over and entering the gaps G1, G2. The iron powder adheres to the yoke 7 and the magnetic bodies 8a and 8b in the gaps G1 and G2 by magnetic attraction. Since the gaps G1 and G2 are formed to have a very narrow facing distance, when iron powder is adsorbed in the gaps G1 and G2, the coils C1 and C2
The vibration due to the electromagnetic force of No. 2 is disturbed, and the insulating coating of the coils C1 and C2 may be damaged.

The present invention is to solve the above-mentioned problems of the prior art. It is possible to firmly fix the members constituting the magnetic circuit and to prevent iron powder from entering the gap portion of the magnetic circuit without the need for tightening screws. The purpose is to provide a speaker that can be prevented and the installation work can be easily performed.

[0011]

According to the present invention, a diaphragm, a coil for vibrating the diaphragm, and a magnetic circuit for applying a magnetic field to the coil are provided in a frame, and the coil constitutes a magnetic circuit. In the speaker located within the facing gap of the member, the mounting member made of a non-magnetic material is inserted between the center hole of the member forming the magnetic circuit and the frame,
The end of the mounting member is caulked to the outer surface of the frame or the end surface of a member forming the magnetic circuit.

In the above, the mounting member can support a small speaker installed on the diaphragm side. The small speaker is, for example, a tweeter, and can be a so-called two-way type speaker.

The mounting member is made of a non-magnetic material such as aluminum or aluminum alloy, brass, zinc alloy, copper or copper alloy. For example, a cylindrical member constitutes a magnetic circuit. The frame is inserted into the center hole of the member and the frame, the end portion of the mounting member is deformed under pressure, and the frame and the member are caulked and fixed by the mounting member.

[0014]

According to the present invention, the mounting member made of a non-magnetic material is inserted into the center hole of the yoke or magnet, which is a member constituting the magnetic circuit, and the hole formed in the frame, and the end portion of this mounting member is caulked and deformed. By doing so, the member forming the magnetic circuit and the frame are caulked and fixed. In this caulking work, metal powder due to screw tightening work is not generated, so metal powder enters the gap of the magnetic circuit,
Problems such as damage to the coil do not occur. Further, since the members forming the magnetic circuit are firmly fixed by caulking, rattling or peeling due to heat deterioration of the adhesive, such as when the members forming the magnetic circuit are fixed only by the adhesive. Such problems do not occur.

The mounting member is made of a non-magnetic material and can be made of resin or the like. However, when the mounting member is made of a non-magnetic metal having good thermal conductivity such as aluminum or aluminum alloy, the coil The heat generated from the portion and accumulated in the portion of the magnetic circuit can be dissipated to the outside of the frame by the attachment member. Further, when the mounting member is formed in a pipe shape, an air flow can be formed in the hollow portion, and the heat radiation effect can be further enhanced.

If the mounting member is extended in the direction of the diaphragm (Y direction) and formed into a cylindrical shape, a small speaker such as a tweeter can be installed thereon. That is, the mounting member is a fixing mechanism of a member forming a magnetic circuit,
It can be used both as a support member for a small speaker such as a tweeter.

Furthermore, when the mounting member is made of a non-magnetic material, the eddy current loss and the hysteresis loss that would occur when using an iron-based metal do not occur, and the adverse effect on the magnetic circuit can be prevented.

Further, the fixing work by crimping is easy and can be automatically carried out.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 1 (a) is a longitudinal sectional view showing a dynamic speaker used in a vehicle as a first embodiment of the present invention when a mounting member is fitted, and FIG. 1 (b) shows mounting. FIG. 2 is a sectional view of the speaker after the members have been caulked.
[FIG. 8] is a sectional view of a speaker showing a second embodiment.

In each of the embodiments shown in FIGS. 1 and 2, in these speakers, the frame 11 is injection-molded from a plastic material such as ABS. Therefore, the entire speaker is lightweight. Further, the frame 11 may be die cast from a lightweight alloy such as an aluminum alloy or a zinc alloy other than plastic.

The vibrating plate 12 has a conical shape (cone shape) formed of a paper material or the like, and a spherical dome portion 13 is joined to the conical head portion 12b. An edge portion of the conical bottom portion 12 a of the diaphragm 12 is joined to the opening edge portion 11 a of the frame 11 via the deformation joining portion 14. Deformation joint 1
The reference numeral 4 is provided separately from the diaphragm 12 along the edge of the conical bottom portion 12b in a circular shape, and its cross-sectional shape is a semicircular shape (semi-cylindrical shape) having a predetermined radius of curvature.

The outer circumference of the conical head portion 12b of the diaphragm 12 is supported by the frame 11 via a damper 15 having a plurality of convoluted corrugated deformation portions. Diaphragm 1
Reference numeral 2 denotes a deformable joint portion 14 and a damper 15, which are oscillatably supported. A bobbin 16 is connected to the conical head 12b of the diaphragm 12. The bobbin 16 is formed by winding a sheet material such as a paper material or a resin material into a cylindrical shape.
A pair of coils (voice coils) C1 and C2 are wound around the outer peripheral surface of the bobbin 16.

Inside the base portion 11b of the frame 11, a ring-shaped member (pole piece) forming the magnetic circuit A1 is housed. A ring-shaped member provided inside the bobbin 16 is a yoke 17, which is made of a magnetic material having a high magnetic permeability such as soft ferrite. The ring-shaped member provided outside the bobbin 16 is a magnet 18. The magnet 18 is a bonded magnet (plastic magnet) in which magnetic powder (magnet powder) is hardened with resin. York 1
Two gaps G1 and G2 are provided in the facing portion between the magnet 7 and the magnet 18.
And the coil C1 is formed in each gap.
And C2 is located. In the magnet 18 in this embodiment, the portion facing the coil C1 is the N pole and the portion facing the coil C2 is the S pole.

At the center of the frame base 11b, the center hole 1
1e is formed. In addition, the frame base 11b,
A step 11d on the outer peripheral side concentric with the center hole 11e is formed. A ring-shaped space B is formed further on the base end side. The space B is formed to secure a moving region of the lower coil C2 and the end 16a of the bobbin 16 which extends through the gap of the magnetic circuit A1 to the base end side. is there.

A method of fixing the yoke 17 which is the inner ring-shaped member constituting the magnetic circuit A1 will be described below.
In the first embodiment shown in FIG. 1A, a mounting member 19 made of a non-magnetic material is used. The mounting member 19 is made of a nonmagnetic metal such as aluminum, aluminum alloy, zinc alloy, or copper alloy, and the flange portion 19a and the pipe-shaped shaft portion 19b are integrally formed. A notch 19c extending in the axial direction is formed at the tip of the shaft portion 19b.
Are formed at a plurality of positions at regular intervals in the circumferential direction.

The outer diameter of the shaft portion 19b of the mounting member 19 is
Center hole 11e of frame 11 and center hole 1 of yoke 17
It is almost the same as the inner diameter of 7a, and the shaft portion 19b is inserted with almost no gap between the center hole 11e and the center hole 17a.

The diaphragm 12 and the damper 1 are provided in the frame 11.
In the process before attaching 5, etc., the frame 1
The yoke 17 is installed on the inner surface of the first base 11b. The shaft portion 19b of the mounting member 19 is inserted into the central hole 17a of the yoke 17 from above in the drawing, and the portion where the notch 19c is formed is projected from the central hole 11e toward the bottom surface of the frame 11. From above and below the mounting member 19, for example, reference numeral 2
When a caulking tool such as Nos. 1 and 22 is fitted and pressed by a press or the like, the portion where the notch 19c at the tip of the shaft portion 19b is formed expands and deforms, as shown in FIG. 1 (b). , Is caulked to the outer surface of the base 11b of the frame 11. The yoke 17 and the frame 11 are sandwiched between the flange portion 19a of the mounting member 19 and the deformed portion by caulking, and the yoke 17 is positioned and fixed with the outer peripheral surface of the mounting member 19 fitted in the center hole 11e as a reference. To be done.

The magnet 1 which is a ring-shaped member on the outer peripheral side
8 is fitted to the step 11d of the frame base 11b so as to be positioned and fixed by an adhesive. The mounting member 19 fixes the yoke 17 constituting the magnetic circuit A1 by caulking and does not require screw tightening work. Therefore, the iron powder does not scatter in the frame 11 during the assembly work, the metal powder enters and adheres in the gap G1 or G2, and the coils C1 and C2 are sandwiched and cannot be moved, or the coils C1 and C2 cannot move. The winding coating is not damaged by metal powder. Further, since the assembling work by caulking can be performed in a short time by a press machine or the like, the assembling work is easy.

Further, when the mounting member 19 is formed of a non-magnetic metal having a good thermal conductivity, when the Joule heat in the coils C1 and C2 is accumulated in the magnetic circuit A1, this heat passes through the mounting member 19. , It becomes easy to diverge to the outside of the frame 11. Therefore, the frame 11 is made of synthetic resin,
Even in the case where the heat of the portion of the magnetic circuit A1 is not easily dissipated from the frame 11 to the outside, the mounting member 19 can be used to obtain a sufficient heat dissipation effect. Also, the mounting member 1
When 9 is a pipe shape, the heat of the magnetic circuit A1 is likely to be radiated by convection through the hollow portion. Further, the pipe-shaped mounting member 19 can be easily deformed when caulking,
The caulking work is easy. Further, by forming the mounting member 19 with a non-magnetic material, it is possible to prevent the occurrence of eddy current loss due to the provision of the mounting member 19.

Mounting member 29 in the second embodiment shown in FIG.
Is formed of a non-magnetic metal as in the first embodiment. The mounting member 29 has a flange portion 29a and a pipe-shaped shaft portion 29b, and the same notch as in the first embodiment shown in FIG. 1 is formed at the tip of the shaft portion 29b. The shaft portion 29b is inserted into the center hole 11e of the frame 11 and the center hole 17a of the yoke 17 without any gap.

The mounting member 29 is formed with a cylindrical portion 29d extending forward from the edge of the flange portion 29a, and the small speaker 23 such as a tweeter is fixed to the cylindrical portion 29d. The mounting member 29 in the second embodiment is the magnetic circuit A
Although the yoke 17, which is the ring-shaped member on the inner side that composes 1, is fixed, the mounting member 29 also has a function as a supporting member that supports the small speaker 23 such as a tweeter.

Also in the embodiment shown in FIG. 2, the magnet 18 has the step 1
It is positioned at 1d and fixed to the frame 11 with an adhesive. In this speaker, the attachment member 29 is inserted into the center hole 17 a of the yoke 17 in a step before the diaphragm 12 and the damper 15 are attached, and the frame 11 is further attached.
Inserted into the center hole 11e of the tool 21 shown in FIG.
It is caulked with 2. After that, the diaphragm 12
The damper 15 is attached, and the small speaker 23 is attached to the attachment member 29.

Also in this embodiment, when the mounting member 29 is caulked, iron powder does not scatter and adhere to the gaps G1 and G2. Further, the mounting member 29 allows the coils C1,
The heat from C2 can also be effectively dissipated. In the second embodiment, the caulking work can be used to easily attach both the member constituting the magnetic circuit and the small speaker.

In the above first and second embodiments,
As for the ring-shaped member forming the magnetic circuit, the one located inside the bobbin 16 may be a magnet, and the one located outside the bobbin 16 may be a yoke. In this case, the attachment member 19 or 29 fixes the magnet 18 by caulking.

Further, in the mounting member 19, the frame 11
The flange portion 19a may be installed on the outer surface side of the, and the mounting member may be press-deformed and caulked at the upper end side of the yoke 17 in the drawing. Further, the diaphragm 12 may not be a cone shape but may be a speaker that emits a sound by vibration of air in the horn.

[0036]

According to the present invention, the members constituting the magnetic circuit can be firmly fixed by the mounting member, the generation of metal powder can be suppressed, and the metal powder does not scatter inside the frame. Therefore, the metal powder can be prevented from adhering to the gap portion of the magnetic circuit.

Further, by using a structure in which the metal powder of the mounting member does not scatter in the frame, and also by using the mounting member as a supporting member for a small speaker such as a tweeter, the parts can be made common.

[Brief description of drawings]

FIG. 1 (a) is a cross-sectional view showing a speaker of a first embodiment of the present invention when a mounting member is fitted, and FIG. 1 (b) is a cross-sectional view showing a mounting member after being caulked;

FIG. 2 is a sectional view showing a speaker of a second embodiment,

FIG. 3A is a cross-sectional view showing a conventional speaker,
(B) is an enlarged sectional view of the magnetic circuit,

FIG. 4 is a cross-sectional view showing another conventional speaker structure.

[Explanation of symbols]

 11 frame 11b frame base 11d frame step 11e center hole 12 diaphragm 13 dome 15 damper 16 bobbin 17 yoke 17a center hole 18 magnet 19, 29 mounting member 19a, 29a flange part 19b, 29b shaft part 19c, 29c cut 29d cylindrical part 21, 22 Caulking tool 23 Small speaker A1 Magnetic circuit C1, C2 Coil G1, G2 Gap

Claims (2)

[Claims] 1. A vibration plate, a coil for vibrating the vibration plate, and a magnetic circuit for applying a magnetic field to the coil are provided in a frame, and the coil is located in a facing gap of a member constituting the magnetic circuit. In the speaker, the mounting member made of a non-magnetic material is inserted between the center hole of the member forming the magnetic circuit and the frame, and the end portion of the mounting member is the outer surface of the frame or the end surface of the member forming the magnetic circuit. A speaker characterized by being crimped. 2. The speaker according to claim 1, wherein the mounting member supports a small speaker installed on the diaphragm side.