JPH08116590A - Speaker and manufacture thereof - Google Patents

Abstract

PURPOSE: To provide the speaker excellent in reliability and cost and its manufacturing method by solving a problem caused by jointing a magnetic circuit and a frame with respect to the speaker to be used for various acoustic equipments. CONSTITUTION: A hollow cylinder 14 projected downward is provided to a center of a frame 11 and the cylinder 14 is fitted to an inner circumferential face 13 of an upper plate 12 forming a magnetic circuit 15. Then the frame is formed to be bent along with the bottom face of the upper plate 12 whose cross section is formed to be a channel shape to improve the reliability due to high adhesion strength and to reduce the cost.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a speaker used in various audio equipment and a method for manufacturing the speaker.

[0002]

2. Description of the Related Art A conventional speaker of this type has a structure as shown in FIGS.

That is, in the speaker shown in FIG.
A frame 4 is welded to an upper plate 2 of a magnetic circuit 5 having a magnetic gap 10 formed by sandwiching a magnet 1 between an upper plate 2 and a lower plate 3 with a center pole, and a voice coil is attached to the frame 4. The speaker was constructed by incorporating the diaphragm 7 which is connected with 6 as the center.

Further, in the speaker shown in FIG. 3, the magnet 1 is connected to the upper plate 2 having a plurality of protrusions 8.
On the upper plate 2A of the magnetic circuit 5A having a magnetic gap 10 formed by being sandwiched by A and the lower plate 3 with the center pole, there are caulking holes 9 that fit into the plurality of protrusions 8 provided on the upper plate 2A. The frame 4A which it has was fitted, and the projection 8 was joined by caulking, and the other structures were the same as those shown in FIG.

In the speaker shown in FIG. 4, the center hole of the frame 4B is formed on the inner peripheral surface of the upper plate 2 of the magnetic circuit 5B in which the magnetic gap 10 composed of the upper plate 2, the magnet 1 and the lower plate 3 is formed. It was crimped and joined, and other configurations were the same as those in FIG.

[0006]

However, the above-mentioned conventional speaker has the following problems in each of the speakers having the configurations shown in FIGS.

First, in the speaker having the structure shown in FIG. 2, since the frame 4 is joined to the upper surface of the upper plate 2 by welding, iron powder is generated due to sparks during welding, and this iron powder is generated by the magnetic circuit 5. It was mixed in the magnetic gap 10 and caused a malfunction.

Further, in the speaker having the structure shown in FIG. 3, the projection 8 provided on the upper plate 2A is utilized to make the frame 4A.
Since it is a method of joining by caulking, the manufacturing process for providing the projections 8 on the upper plate 2A requires an additional process, which is expensive in terms of cost.

Further, the joining of the upper plate 2A and the frame 4A has a very long process as compared with the joining method by welding shown in FIG.

Further, in the speaker having the structure shown in FIG. 4, since the frame 4B is swaged into the upper plate 2 of the magnetic circuit 5B by swaging, the weight of the magnetic circuit 5B is large. There was a risk of disbonding.

The present invention solves these conventional problems,
An object of the present invention is to provide a speaker that reduces defects due to the joining of the upper plate and the frame, that is, defects due to the mixing of the iron powder and the joining of the magnetic circuit, and is inexpensive in cost.

[0012]

In order to solve the above-mentioned problems, the speaker of the present invention forms a magnetic gap by stacking a ring-shaped magnet and a ring-shaped upper plate on a lower plate having a center pole. A magnetic circuit, a frame which is coupled to the upper surface of the magnetic circuit and whose central portion is bent in a U-shaped cross section along the inner peripheral surface and the bottom surface of the upper plate, and the outer peripheral portion is coupled to the peripheral edge of the frame. At the same time, the configuration is made up of a vibration plate having a voice coil fitted in the magnetic gap and coupled to the center thereof.

[0013]

With the above structure, it is not necessary to weld the magnetic circuit and the frame to each other, and therefore, it becomes possible to avoid a defective iron powder mixture due to sparks or the like caused by variations during welding work.

Even when a heavy magnetic circuit is used, since the upper plate is wrapped in the frame due to its structure, the joining strength is high, and it is necessary to add an extra step in the joining process of the upper plate and the frame. Moreover, an inexpensive and highly reliable speaker can be obtained.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a front sectional view showing the structure of the speaker according to the present embodiment. As shown in FIG. 1, a downwardly projecting hollow cylindrical portion 14 provided at the center of a frame 11 has a ring-shaped upper portion. The upper plate 12 is fitted along the inner peripheral surface 13 of the central hole of the plate 12, and the tip of the cylindrical portion 14 is bent along the bottom surface of the upper plate 12 into a U-shaped cross section so that the upper plate 12 is sandwiched and coupled. A magnetic circuit 15 is formed by laminating a frame 11 and a ring-shaped magnet 16 and a lower plate 17 with a center pole on the lower surface of an upper plate 12 coupled to the frame 11 to form a magnetic gap 22.

The periphery of the frame 11 connected to the magnetic circuit 15 is connected to the periphery of the diaphragm 19 together with the gasket 18, the voice coil 20 is connected to the center of the diaphragm 19, and the voice coil 20 is connected to the voice coil 20. Is supported by a damper 21 so that the lower portion of the voice coil 20 is fitted into the magnetic gap 22 of the magnetic circuit 15 without being eccentric, and the dust cap 23 is provided on the upper surface of the central portion of the diaphragm 19.
Is attached to form a speaker.

As a method of manufacturing this speaker,
A frame 11 having a hollow cylindrical portion 14 protruding downward from the central portion is prepared. The frame 11 can be formed with the cylindrical portion 14 by press working so that the portion forming the central hole is projected downward.

The cylindrical portion 14 of the frame 11 is fitted in the center hole of the ring-shaped upper plate 12, and the cylindrical portion 14 is bent outward by pressing so as to hold the inner peripheral surface 13 of the upper plate 12. The frame 11 and the upper plate 12 are joined together.

The upper plate 12 is placed on the magnet 16 fixed to the lower plate 17 having a center pole, and is bonded with an adhesive.

The outer peripheral portion of the diaphragm 19 having the voice coil 20 connected at the center is attached together with the gasket 18 to the peripheral portion of the frame 11 of the magnetic circuit 15 thus constructed.
The peripheral portion of the damper 21 coupled to the middle portion of the voice coil 20 is attached to the inner bottom surface of the frame 11,
0 is fitted into the magnetic gap 22 of the magnetic circuit 15 without eccentricity, and finally the dust cap 23 is attached to the upper surface of the central portion of the diaphragm 19 to assemble the speaker.

[0022]

As described above, according to the speaker and the manufacturing method thereof according to the present invention, the lower portion of the cylindrical portion projecting downward from the central portion of the frame around the central hole of the upper plate is sandwiched by being bent outward. Not only does the iron powder mixture defect in the conventional joining method not occur, but the joining defect does not occur even when a heavy magnetic circuit is used.

Further, the frame and the upper plate to be used do not require any additional steps in manufacturing, the defects due to the joining of the upper plate and the frame can be reduced, and the material of the upper plate is required to have a magnetic pole width. Since it is possible to increase the number, it is possible to easily provide a speaker that is inexpensive and has high reliability.

[Brief description of drawings]

FIG. 1 is a front sectional view showing the configuration of a speaker according to an embodiment of the present invention.

FIG. 2 is a front sectional view showing a speaker having a structure in which a conventional upper plate and a frame are joined together by a welding method.

FIG. 3 is a front sectional view showing a speaker having a configuration in which a plurality of protrusions are provided on a conventional upper plate and caulked and joined to a frame.

FIG. 4 is a front sectional view showing a speaker in which a conventional upper plate and a frame center hole are crimped and joined together.

[Explanation of symbols]

 11 Frame 12 Upper Plate 13 Inner Surface of Upper Plate 14 Cylindrical Part 15 Magnetic Circuit 16 Magnet 17 Lower Plate 18 Gasket 19 Vibration Plate 20 Voice Coil 21 Damper 22 Magnetic Gap 23 Dust Cap

Claims (2)

[Claims] 1. A magnetic circuit in which a ring-shaped magnet and a ring-shaped upper plate are laminated and coupled to form an upper portion of a lower plate having a center pole to form a magnetic gap, and a magnetic circuit coupled to the upper surface of the magnetic circuit and at the center. From a diaphragm in which a frame is formed by bending the inner plate along the inner peripheral surface and the bottom surface of the upper plate in a U-shaped cross section, and the outer peripheral portion is connected to the peripheral edge of the frame, and a voice coil is fitted around the magnetic gap. Become a speaker. 2. A downwardly projecting hollow cylindrical portion provided in a central portion of a frame is fitted into an inner circumference of a ring-shaped upper plate, and a tip end of the cylindrical portion is circumferentially extended along a bottom surface of the upper plate. The frame and the upper plate are joined by bending to a frame, and the lower plate having the ring-shaped magnet and the center pole is laminated and joined to the lower surface of the upper plate to which the frame is joined to assemble a magnetic circuit in which a magnetic gap is formed. While connecting the outer peripheral part of the diaphragm that has the voice coil connected to the center to the peripheral edge of
The method of manufacturing a speaker according to claim 1, wherein the voice coil is fitted in the magnetic gap without being eccentric to assemble the speaker.