JPH078072B2 - Magnetic circuit member support structure for vibration unit - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention provides an audio reproduction effect by air propagation from a speaker as well as an audio signal for driving the speaker, in order to make it possible to sense deep bass more ideally. , For example, 150H
A low-range audio signal below Z is converted into mechanical vibration, and by vibrating this in synchronization with speaker playback, a vibration unit that generates mechanical vibration to further enhance the sense of presence, In particular, the present invention relates to a support structure that supports a magnetic circuit member of a vibration unit.

[0002]

2. Description of the Related Art Conventionally, in this type of vibrating unit, a magnetic gap is formed by a yoke having magnetic poles, a voice coil is arranged in the gap, and an audio in a low range is applied to the voice coil. It has been proposed to obtain mechanical vibration by a magnetic interference action generated between a magnetic force generated in a voice coil and a magnetic force of a magnetic pole due to a signal.

As one means for propagating (outputting) the mechanical vibration of the vibrating unit to the diaphragm or the like, the yoke is supported in the case body of the vibrating unit via a damper, and the yoke and the case body are relatively displaced. In addition to the above structure, the case body is attached as a mounting member to a diaphragm or the like to output mechanical vibration. (See, for example, Japanese Patent Publication No. 58-9640).

In a structure such as this vibrating unit that outputs mechanical vibration through the case body, it is necessary to support the yoke in the case body so that the yoke can be swung in the vibration direction. As a supporting means for the yoke, one damper is positioned so as to be horizontal to the voice coil in a plane including a space where the voice coil is located (see, for example, Japanese Patent Publication No. 58-9640). ),
Alternatively, two dampers (for example, Japanese Patent Publication Sho 62
No. 33799).

Further, as another yoke supporting means, one having a structure for supporting the yoke by using a spring member provided in the case body (for example, refer to Japanese Patent Laid-Open No. 61-67400), or this spring member. There is a structure bent into a U-shape (for example, see Japanese Patent Laid-Open No. 63-197198, particularly FIG. 3 and its description).

[0006]

In the conventional vibration unit, the structure in which the yoke is supported in the case main body through one ring-shaped damper is a magnetic circuit member composed of a magnet, a yoke and the like. Since the positional relationship with the voice coil is supported by a single ring-shaped damper, the voice coil and the magnetic circuit member, which are constantly displaced in the exciting direction relative to each other when the vibration occurs, are in the non-exciting direction. Positional deviation, that is, kinking occurs, and the voice coil and the yoke of the magnetic circuit member come into contact with each other to cause abnormal noise. This is a serious problem particularly in a structure in which a heavy magnetic circuit member is vibrated unlike a general speaker that vibrates a lightweight voice coil.

As one means for solving such inconvenience, it is conceivable to absorb the above-mentioned displacement by setting a wide gap between the voice coil, the yoke and the pole piece in advance. However, if the gap between the two is widened, the magnetic influence will decrease,
This has the disadvantage of affecting the electromagnetic performance and significantly reducing the vibration efficiency.

In order to solve such an inconvenience, a structure has been proposed in which two dampers are used to support a magnetic circuit constituent member such as a yoke. However, in such a structure, May cause abnormal vibration due to the resonance of the dampers.

As a magnetic circuit member supporting structure by another means, there is a structure in which a ring-shaped spring member is attached to the outer periphery of the yoke, and the yoke is supported by the case body by the ring-shaped spring member. This is also 1
Similar to the structure using a single damper, there is a disadvantage that the voice coil and the magnetic circuit member are displaced from each other in the non-excitation direction. If the ring-shaped spring member is made thicker in order to eliminate this inconvenience, the vibrating operation of the magnetic circuit member is suppressed, and the vibration efficiency is deteriorated and the resonance frequency f0 becomes high.

Further, in the structure in which the yoke is suspended on the U-shaped bent spring member, one end of the U-shaped spring member is attached to the inside of the case body, so that the suspension is performed. When the yoke is vibrated, the spring member may be biased in the mounting direction, so that the yoke may come into contact with the voice coil and generate abnormal noise. Also, because the yoke is suspended by a spring member, it is a structure that is very difficult to align with the voice coil, and it is easily affected by external impacts, and the case body also becomes large, and downsizing is especially required. It is not suitable as a vibrating unit used in a vehicle body acoustic sensor.

The present invention provides a novel magnetic circuit member supporting structure that solves various problems of the above-described conventional magnetic circuit member supporting structure of the vibration unit. To prevent deviation of the positional relationship between the yoke and the voice coil that fluctuate in the vibration direction with respect to the non-vibration direction, that is, to prevent kinking, improve vibration efficiency and vibration propagation efficiency, and obtain sufficient deep bass vibration. It is an object of the present invention to provide a magnetic circuit member supporting structure of a vibration unit capable of performing the above.

[0012]

In order to achieve the above object, in the magnetic circuit member supporting structure of the vibration unit of the present invention, a magnetic gap is formed by a yoke having magnetic poles, and a magnetic gap is formed in the gap. A vibration unit in which a voice coil is arranged and mechanical vibration is obtained by a magnetic interference effect generated between a magnetic force generated in the voice coil and a magnetic force of a magnetic pole accompanying an audio signal applied to the voice coil. The both ends of an elastic plate damper having an elongated flat plate shape having a yoke attached to the center thereof are sandwiched between elastic support fittings so as to be swingably supported.

Further, the plate damper is formed with knife edge portions at both ends thereof so as to be swingable.

Further, one end portion of the elastic support metal fitting is provided with a mounting portion to the frame, and the other end portion thereof has a dogleg shape for receiving a knife edge portion provided at an end portion of the plate damper. The support part formed by bending is provided.

[0015]

When a low-pitched audio signal is applied to the voice coil of the vibrating unit, a magnetic force is generated in the voice coil along with the applied audio signal, and due to a magnetic interference action generated between the voice coil and the magnetic force of the magnetic pole, A yoke attached to a plate damper having an elongated flat plate elasticity,
The frame to which the voice coil is attached is displaced relative to the frame to generate mechanical vibration.

At this time, the plate damper flexes slightly in the vibration direction from the horizontal state in accordance with the vibrating operation of the yoke, then returns to the horizontal state again, and then a series of vibrating motions of slightly bending to the opposite side are continued. To do. Along with the oscillating movement of the plate damper, both end portions of the plate damper, that is, the portion acting as the fulcrum, expands and contracts by repeating a slight movement in the horizontal direction while swinging. However, since both ends are supported by elastic support fittings so as to be sandwiched from both sides, the support fittings follow the expansion and contraction operation caused by the swinging of both ends in the vibration direction. Absorbs.

[0017]

EXAMPLES Examples will be described with reference to the drawings. 1 to 5 show a first embodiment of a magnetic circuit member supporting structure according to the present invention. FIG. 1 is a perspective view in which a part of a vibration unit in which the magnetic circuit member supporting structure of the present invention is implemented is cut away, and FIG. 2 is a sectional view of FIG. 3 is an enlarged cross-sectional view of an essential part of the left side portion of FIG. 1, FIG. 4 is a perspective view showing the left end portion of the plate damper, and FIG. 5 is a support for swingably supporting the end portion of the plate damper in the vibration direction. It is a perspective view of a metal fitting.

In the figure, reference numeral 1 denotes a frame having a U-shaped cross section, which is made of a metal such as aluminum and long in the lateral direction. A voice coil 2 is arranged inward at the center of the frame 1, and the voice coil 2 is wound around a bobbin 3. The insulating substrate 4 fitted and attached to the bobbin 3 is attached to the fixed plate 5. By adjusting the mounting position of the fixed plate 5 with respect to the frame 1, the voice coil 2 can be correctly arranged in the magnetic gap of the yoke 6. 7
Is a terminal to which the voice coil 2 is connected. An audio signal in the low range is applied to this terminal 7 and supplied to the voice coil 2.

Next, the yoke 6 provided with the magnet 8 will be described. The yoke 6 is formed of a columnar member having a concave cross section, and the magnet 8 is fixed to the inner center position of the yoke 6 in a loosely fitted state. Therefore, a magnetic annular gap is formed between the magnet 8 and the inner wall surface of the columnar member having a concave cross section to form a magnetic circuit.
Then, the voice coil 2 is arranged in this void. Further, the yoke 6 is provided so that the voice coil 2 can be always arranged in the correct position in the air gap.
It is fixed to the center of the plate damper 9.

The plate damper 9 has a rectangular cross-section to prevent twisting in the non-exciting direction, and is a plate-like elastic material made of metal such as an elongated flat aluminum plate, brass, stainless steel or the like having a sufficient thickness. Is formed by. The plate damper 9 is positioned so as to be horizontal with respect to the voice coil 2, and both ends 9A and 9B thereof are arranged and supported apart from the frame 1.

Next, a plate damper 9 in which a magnetic circuit member consisting of a yoke 6 having a magnet 8 is fixed to the center portion
A first embodiment of the supporting structure will be described with reference to FIGS.

First, the end portion 9A of the plate damper 9 (the other end portion 9B has the same structure, so the description thereof will be omitted) is formed in a U shape, and the plate damper 9 is formed.
Forming two protrusions 10 and 11 parallel to the longitudinal direction of. The two protrusions 10 and 11 are for preventing the plate damper 9 from swinging in the non-exciting direction by the inner surfaces 10A and 11A facing each other. Further, a knife edge portion 12 is formed at the inner edge portion orthogonal to the inner surfaces 10A and 11A facing each other.

On the other hand, the support fitting 13 that supports the end portions 9A and 9B of the plate damper 9 so as to be swingable in the vibration direction in a state of being separated from the frame 1 is made of an elastic metal material and has one end portion thereof. A support portion 14 for receiving the knife edge portion 12 of the plate damper 9 is formed by bending it into a dogleg shape. In addition, the support portion 14 is provided on the inner surface 10 of the projecting portions 10 and 11 of the plate damper 9 that face each other.
It is formed with a width substantially equal to the distance between A and 11A. Therefore, the knife edge portion 12 is supported by the support portion 14,
The end portions 9A and 9B of the plate damper 9 are made swingable in the vibration direction, and at the same time, both side surfaces 14A, 1 of the support portion 14 are formed.
The contact between 4B and the inner side surfaces 10A and 11A of the projections 10 and 11 prevents the end portions 9A and 9B of the plate damper 9 from swinging in the non-exciting direction.

The mounting of the support fitting 13 thus configured to the frame 1 is performed as follows. First, the end portion side of the support fitting 13 provided with the screw hole 16 is inserted into the mounting hole 15 provided in the frame 1, the screw 17 is passed through the screw hole 16 and fixed to the mounting portion 18 of the frame 1. At the time of this attachment, the support fitting 13 has its support portion 14 inserted between the protrusions 10 and 11 of the plate damper 9, and the V-shaped portion of the support portion 14 is aligned with the knife edge portion 12 to form a knife. The edge portion 12 is received while being strongly pressed. Therefore, the plate damper 9 has two end portions 9A and 9A.
It is spaced from the frame 1 and is horizontally supported with respect to the voice coil 2 while being strongly sandwiched from both sides by the support fittings 13 arranged in B. On the other hand, the support fitting 13
Is fixed to the mounting portion 18 so as to strongly sandwich both ends 9A and 9B of the plate damper 9, so that the support fitting 13
Due to its own elasticity, it flexes slightly outward and retains its force.

In the vibrating unit having the support structure constructed as described above, when an audio signal in the low range of 150 Hz or less is applied to the voice coil 2, a magnetic force is generated in the voice coil 2 based on the applied audio signal. To do. Due to the magnetic interference generated between the magnetic force of the voice coil 2 and the magnetic force of the magnet 8, the yoke 6 attached to the plate damper 9 and the frame 1 attached to the voice coil 2 are relatively displaced to cause mechanical vibration. Can occur. This mechanical vibration is propagated to the entire frame 1 and can be taken out (output) from the side surface 1A located in the vibration direction of the frame 1.

At this time, the plate damper 9 slightly bends in the vibration direction from the horizontal state as the yoke 6 vibrates, then returns to the horizontal state again, and then continuously bends slightly to the opposite side. Make an oscillating motion. In accordance with such an oscillating movement of the plate damper 9, both end portions 9A, 9B of the plate damper 9, that is, a portion acting as a fulcrum, expands and contracts by repeating a slight horizontal movement while swinging. do. However, both ends 9A and 9B are
Since it is supported so as to be sandwiched from both sides by the elastic support metal fittings 13, the support metal fittings 13 can perform a follow-up operation to absorb the expansion and contraction motion caused by the swinging of the both end portions 9A and 9B, and thus support. it can.

Next, a second embodiment of the magnetic circuit member supporting structure of the present invention shown in FIGS. 6 to 8 will be described. In the second embodiment, both end portions 9A and 9A of the plate damper 9 are
Another structure for supporting B so that it can swing is proposed. The same parts as those in the first embodiment shown in FIGS. 1 to 5 described above are designated by the same reference numerals and the description thereof will be omitted.

The support fitting 19 in the second embodiment
Is provided with a screw hole 16 for attaching to the attachment portion 18 of the frame 1 at one end, and two projecting portions 1 provided at the ends 9A (and 9B) of the plate damper 9 at the other end.
U-shaped support portions 20 and 21 opened outward are provided at positions substantially equal to the distance between 0 and 11.
By engaging the protrusions 10 and 11 with the U-shaped bearings 20 and 21, it is possible to swing the plate damper 9 in the vibration direction and prevent the vibration in the non-vibration direction. can do.

In addition, in order to improve the swinging motion of the end portions 9A (and 9B) of the engaged plate dampers 9, the bearing portions 20 and 21 have a pair of opposing knife edge portions 20.
A, 20B and 21A, 21B are provided. Further, the knife edge portion 12 formed on the end portion 9A (and 9B) of the plate damper 9 comes into contact with one side surface of the support fitting 19 so that the plate damper 9 can be swung smoothly. .

[0030]

As described above, according to the magnetic circuit member supporting structure of the present invention, the yoke can be fixed in advance to the central portion of the elongated flat plate damper, so that it is horizontal to the voice coil. As described above, the yoke is mounted and positioned only by supporting both ends of the plate damper so as to be separated from the frame, and the positional relationship can be accurately and quickly determined.

Further, since the supporting metal fittings for strongly sandwiching the plate damper from both sides are formed of elastic members, both ends of the plate damper, that is, the portion acting as a fulcrum, is vibrated in the vibration direction. The follow-up operation is performed so as to absorb the expansion / contraction operation caused by the movement, and both ends of the plate damper can be reliably supported.

Further, since both ends of the plate damper are supported by the support fittings so as to be swingable in the vibration direction, the plate damper can be efficiently vibrated in the vibration direction. Further, the engagement of the end portion of the plate damper and the support fitting can suppress the displacement of the plate damper in the non-exciting direction, and can prevent the yoke from contacting (contacting) the voice coil. Can be vibrated stably with respect to the voice coil.

Further, in the case of a structure in which one end of a conventional spring member having a suspended yoke is fixed, the resonance frequency characteristic of the vibration is sharp determined by the mass of the magnetic circuit member and the spring material supporting it. Although it has a resonance characteristic, the response operation characteristic to an input signal is further improved by adopting a structure in which both ends of the plate damper are supported so as to be swingable in the vibration direction like the support structure of the magnetic circuit of the present invention And the length, mass of the plate damper,
By selecting the material and the like, it is possible to obtain vibration characteristics having a predetermined amplitude in a wide frequency band.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view showing an embodiment of a magnetic circuit member supporting structure of the present invention.

2 is a cross-sectional side view of the embodiment shown in FIG.

3 is a cross-sectional side view of essential parts of the embodiment shown in FIG.

4 is an enlarged perspective view of one end of a plate damper used in the embodiment shown in FIG.

5 is a perspective view of a support fitting used in the embodiment shown in FIG. 1. FIG.

FIG. 6 is a partially cutaway perspective view showing a second embodiment of the magnetic circuit member support structure of the present invention.

7 is a sectional side view of the embodiment shown in FIG.

FIG. 8 is a perspective view of a plate damper and a support fitting used in the embodiment shown in FIG.

[Explanation of symbols]

1 is a frame. 2 is a voice coil. 3 is a bobbin. Reference numeral 4 is an insulating substrate. Reference numeral 5 is a fixed plate.
6 is a yoke. 7 is a terminal. 8 is a magnet. 9 is a plate damper. 9A is one end of the plate damper 9. 9B is the other end of the plate damper 9. Reference numeral 10 is a protrusion. Reference numeral 11 is a protrusion. 1
2 is a knife edge part. Reference numeral 13 is a support fitting. 1
4 is a bearing unit. Reference numeral 15 is a mounting hole. 16 is a screw hole. 17 is a screw. Reference numeral 18 is a mounting portion. 19
Is a support fitting.

Claims (2)

[Claims] 1. A magnetic gap is formed by a yoke having a magnetic pole, a voice coil is arranged in the gap, and a magnetic force and a magnetic pole generated in the voice coil in accordance with an audio signal applied to the voice coil. In a vibrating unit configured to obtain a mechanical vibration by a magnetic interference action generated between the plate and the elastic plate damper having a slender flat plate shape having a yoke attached to the center thereof, both ends of the plate are elastically supported. A vibration unit characterized by being sandwiched between metal fittings and supported so as to be swingable, and configured to follow the expansion and contraction movement caused by the swinging of both ends of the plate damper in the vibration direction and absorb the expansion and contraction. Magnetic circuit member support structure. 2. A support part is formed by bending an elastic metal support into a dogleg shape, and the support part swingably supports the knife edges formed at both ends of the plate damper by the support part. The magnetic circuit member support structure of the vibration unit according to claim 1, wherein the structure is as described above.