JPH0727758Y2 - Speaker unit - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a speaker unit, and in particular, uses a high-performance magnet as an inner magnet type to reduce leakage magnetic flux.
The top plate is eliminated from the magnetic circuit to eliminate the emission of unwanted vibration sound.

[Conventional technology]

FIG. 2 is a vertical sectional view of a conventional outer magnet type speaker unit. In the figure, (1) is a diaphragm, (2) is its suspension, and the magnetic flux is on the top plate (4) side of the magnet (3). The main loop is to start from the top plate (4), fly to the center pole (5), and return to the magnet (3) through the bottom plate (6), but the outer peripheral surface of the magnet (3) is exposed. Therefore, there are many so-called leakage magnetic fluxes that fly from the top plate (4) toward the bottom of the magnet (3) or toward the bottom plate (6), and the magnetic force is not only for other electrical components but also for the net of own system. It also affects the work. Further, since the outer diameter of the above magnet is large, the outer diameter of the top plate (4) is also increased accordingly, so that unnecessary vibration sound is emitted from this portion and the reproduced sound is contaminated. In the figure, (7) is a mount for the suspension (2) provided on the top plate (4).

[Problems to be solved by the invention]

The magnet in the conventional speaker unit is a large outer magnet type, and the top plate becomes large accordingly, and the front projected area becomes large. Therefore, there are many leakage magnets and unnecessary vibration noise is generated. There was a problem that it radiated a lot.

The present invention aims to eliminate the above-mentioned problems by making the magnet used to be an inner magnet type and eliminating the top plate from the magnetic circuit.

[Means for solving problems]

In the case of this invention, a high-performance Nd-FeB magnet, for example, is used as the magnet of the speaker unit, and the outer circumference of the yoke is surrounded by a yoke as an inner magnetic structure, and the suspension of the diaphragm is attached to the outer peripheral edge of the yoke. I have attached a shion.

[Action]

In this invention, the magnet of the speaker unit is formed into an inner magnet type magnetized in the radial direction and the outer peripheral surface is surrounded by a yoke, so that the leakage magnet is reduced and the top plate is eliminated from the magnetic circuit. As a result, there is no emission of unnecessary vibration sound from this top plate.

〔Example〕

An embodiment of the present invention will be described below. That is, in FIG. 1, (1) is a diaphragm, (2) is a suspension for elastically supporting the outer peripheral edge of the diaphragm, and its fixed end is a yoke (8) forming a part of a magnetic circuit. Is superposed and fixed on a flange (9) for attachment to an enclosure formed on the outer peripheral edge of the. Further, (9a) in the figure is an annular notch formed in the inner peripheral surface of the rim of the central recess (8a) provided in the yoke (8) for escape against the vibration amplitude of the suspension (2). It is a department. Furthermore (10)
A high-performance magnet such as an Nd-FeB magnet, which is, for example, a ring-shaped or disk-shaped magnet, is magnetized in the radial direction so that the center part thereof becomes the S pole and the outer peripheral part becomes the N pole, and the voice coil ( The outer peripheral surface (10a) facing the central recess (8a) of the yoke (8) forming the magnetic gear cup (G) into which the (11) is inserted is formed on the lower half outer peripheral surface thereof as shown in the figure. The part (10b) is formed.

That is, since the magnet (10) in the speaker unit of the present invention is formed with the annular notch (10b) as described above, the magnetic resistance to the magnetic flux passing through this notch (10b) is The magnetic flux distribution is larger than that at the upper half outer peripheral surface (10a) forming (G), and the magnetic flux distribution gathers at this upper half outer peripheral surface (10a).
The magnetic flux density at is increased and the sound pressure level of the speaker is increased. Further, in the case of this invention, the suspension (2) is directly attached to the flange (9) so that the conventional top plate (4) and the mounting base (7) are eliminated from the magnetic circuit.

In the above embodiment, the annular notch (9a) is formed in a stepped shape to escape the vibration amplitude of the suspension (2) provided on the yoke (8), but this is simply formed in a tapered shape. You may. Also magnet (10) and yoke (8)
The hole at the center of and exists in the case of the mid-range speaker unit (squaker), so the magnet becomes an annular shape, but it is eliminated in the high-range speaker unit (tweeter). It is obvious that the magnet in that case has a disk shape.

[Effect of device]

As described above, according to the present invention, a magnet having an annular or disk shape and being magnetized in the radial direction and provided with an annular notch portion retreated from the outer peripheral surface near the back surface is connected to a diaphragm having a suspension. And a voice coil that is arranged with a gap on the outer peripheral surface of the magnet, and a central recess that is formed by retracting and the back surface of the magnet is attached to the bottom surface and the inner surface forms a gap on the outer peripheral surface of the voice coil , An annular notch formed in the opening of the central recess and formed in the outer circumferential direction from the opening edge, and the notch surface is arranged to coincide with the surface of the magnet, and the notch above the notch. And a yoke having a flange that is connected to the edge and has a mounting hole for mounting an enclosure, and a suspension of the vibration plate is fixed to the yoke.

This not only reduces the leakage magnetic flux, but also eliminates the emission of unwanted vibration noise due to the elimination of the top plate. Furthermore, the outer circumference of the lower half of the magnet except the upper half outer circumferential surface forming the magnetic gear is eliminated. By shaving the surface, it is possible to obtain an effect that the reproduced sound pressure level can be improved.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of the speaker unit of the present invention, and FIG. 2 is a vertical sectional view showing a conventional speaker unit. In the figure, (1) is a diaphragm, (8) is a yoke, (8a) is a central recess, (9) is a flange, (10) is a magnet, (10a) is an outer peripheral surface, and (10b) is a notch. , (11) is a voice coil,
(G) is a magnetic gear.

Claims (1)

[Scope of utility model registration request] 1. A magnet having an annular or disk shape, magnetized in the radial direction, and provided with an annular notch that is retreated from the outer peripheral surface near the back surface, and a diaphragm having a suspension are connected to each other to connect the magnet. A voice coil arranged with a gap formed on the outer peripheral surface, and a central recess that is formed by being retracted and the back surface of the magnet is attached to the bottom surface, and the inner surface forms a gap on the outer peripheral surface of the voice coil to face each other, An annular notch provided in the opening of the central recess and formed in the outer peripheral direction from the opening edge, and the notch surface is arranged so as to coincide with the surface of the magnet, and the upper edge of the notch. And a yoke having a flange to which the suspension of the diaphragm is fixed, the mounting unit being provided with a mounting hole for mounting an enclosure.