JPH02257800A - Speaker - Google Patents

Abstract

PURPOSE:To transduce a given electric vibration change into a change in an acoustic output with fidelity by arranging magnets of a speaker as checkers and driving a planar diaphragm not subject to limit of area entirely. CONSTITUTION:When magnets 8 are arranged as checkers so that N poles 1 and S poles 2 are opposite to each other, the surrounding of the N poles 1 is all S2 poles and the S poles 2 are all surrounded by the N poles 1. Since a prescribed interval is kept between the poles, a magnetic field from the N pole 1 to the S pole 1 is formed among all the poles and when a voice coil 5 is inserted in the magnetic field and a current flows thereto, the voice coil 5 is moved in the axial direction. Since lots of the magnets 8 are arranged to the diaphragm 6 and the voice coil 5 is coupled directly to one diaphragm 6 to exert uniform force to the entire diaphragm 6 in this way and the diaphragm 6 is vibrated by the full face drive system, then not only high pitched tone but also low pitched tone is reproduced with fidelity.

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention is characterized by arranging the magnets of the speaker like the eyes of the base, so that the flat diaphragm, which is not subject to area limitations, can be driven over its entire surface. The present invention relates to a speaker that can more faithfully lead electrical vibration changes into acoustic output changes, and can widen the directivity by adding an arbitrary inclination to the diaphragm.

[Prior Art] Currently, there are various types of speakers, such as dynamic type, magnetic type, condenser type, ion type, and crystal type. Let's talk about the direct radiation type.

Its structure is based on Fleming's left-hand rule, which states that when a conductor is placed in a magnetic field and a current is passed through it, a force is exerted on the conductor.The voice coil is immersed in the magnetic field, and when a voice current flows through the voice coil, the coil responds accordingly. causes motion in the axial direction,
The sound is then radiated by moving a diaphragm connected directly to the coil.

[Problems to be Solved by the Present Invention] The problem with the conventional dynamic direct radiation type speaker described above is that it uses a center drive system using a voice coil.

When reproducing high-pitched sounds, the diaphragm can be small, so it is relatively simple, but when reproducing low-pitched sounds with the same diaphragm, due to the wavelength, unless it is placed close to the ear,
It cannot be emitted as sound.

Therefore, when reproducing low frequencies, the area of the diaphragm must be increased.

The bigger it gets, the heavier it becomes, and the law of inertia comes into play, making it impossible to move quickly and making it difficult to reproduce high-pitched sounds.

In order to faithfully reproduce not only high-pitched sounds but also low-pitched sounds, the diaphragm needs to be as light as possible, so materials such as paper are used, but these materials have zero rigidity when in a flat state. Even if you attach a voice coil to the center of the diaphragm and vibrate the diaphragm, you cannot vibrate the entire diaphragm.

Therefore, the diaphragm is made into a conical shape to give it more rigidity, but this creates a cavity effect that causes distortion in the sound.

Furthermore, even if the shape is conical, if the frequency exceeds a certain level, it becomes difficult to move as a unit, causing split vibrations, which also prevents faithful sound reproduction.

In addition, as a result of increasing the area of the diaphragm for bass reproduction,
In most cases, the edges of the diaphragm are fixed, but for this reason, the vibrations moving from the center of the diaphragm toward the edges and the vibrations reflected from the fixed edges interfere with each other, which also causes sound distortion. It becomes.

In recent years, in order to suppress split vibration, there have been many methods such as driving four nodes or using a flat diaphragm to eliminate cavity effects, etc., but there are many problems such as weight, rigidity, split vibration, vibration interference, etc. The problem is not ideally solved.

Therefore, in order to compensate for these shortcomings even if only a little, speakers for high sound, medium sound, and low sound are often combined into a single speaker system.

However, it is not possible to completely solve the above problems, and on the contrary, because the receiver is divided depending on the frequency, the bass range is distorted for the treble, the high and low range are distorted for the midrange, and the treble range is distorted for the bass. is reproduced with distortion, so it is difficult to say that the given electrical vibration changes are faithfully led to changes in the acoustic output.

Another essential aspect of speaker performance is sound directionality.

As the frequency increases, the directivity becomes narrower, so in the case of system speakers, the toewie is often dome-shaped, but since the squawker has a conical diaphragm, it cannot be said that the directivity is good.

However, the woofer is not so much of a problem since the directivity of the bass is wide.

Therefore, the present invention minimizes the weight of the above-mentioned problems, and
The design eliminates vibration reflection from the edges of the diaphragm to eliminate split vibrations and cavity effects, eliminates vibration interference, and does not limit the area of the diaphragm so that it can accommodate all frequencies. In order to further improve directivity, the diaphragm can be freely angled.

[Means for Solving the Problems] The structural principle of the speaker of the present invention is the same as that of the dynamic direct radiation type described above, but as a means to solve the above-mentioned problems, it is possible to use a central drive method or four-position speaker as in the past. The diaphragm is vibrated by a full-surface drive system, rather than by a slight drive.

The method is to arrange many magnets over the entire diaphragm instead of just one as in the past, and connect the accompanying voice coil directly to one diaphragm so that a uniform force is applied to the entire diaphragm. do.

Of course, installing a large number of conventional vibration generators may have some effect, but because conventional dynamics beakers create a magnetic field with the center ball and yoke, the distance between voice coils increases, and one voice The area of the coil receiver becomes large, making it unable to adequately handle high frequencies, and for the same reason, the problem of vibration interference due to split vibrations and reflected vibrations cannot be solved.

Therefore, as stated in the claims, if the poles of the magnet are arranged like the eyes of the base and a voice coil is placed on each pole, the area of the diaphragm that one voice coil has is The cross-sectional area is equal to that of the voice coil, and even though it does not have complete full-plane drive like a condenser type or ribbon speaker, it brings out the advantages of full-plane drive, and on top of that, the voice coils and the diaphragm are integrated. By increasing the rigidity of the vibrating part, it compensates for the drawbacks of the conventional dynamic type.

[Embodiments and Operations] The structure and operations of the speaker of the present invention will be described below with reference to drawings showing embodiments thereof.

If the magnets in Figure 1 are arranged in the same pattern as the base, with the N and S poles facing each other as shown in Figure 4, everything around the N pole becomes an S pole, and everything around the S pole becomes an N pole. becomes.

Since the poles are kept at a constant distance, a magnetic field is created between them all from the north pole to the south pole.

If the voice coil shown in Figure 5 is inserted into the magnetic field and a current is applied, the voice coil will move in the axial direction according to Fleming's left hand rule.

The N-pole voice coil and the S-pole voice coil must move in the same direction, so when the N-pole voice coil is clockwise-wound, the S-pole voice coil is left-wound so that the current flows in opposite directions. and connect directly to the − diaphragm.

By applying current to the voice coil in this way, the diaphragm will move in the same direction with the same force no matter where it is placed.

However, the voice coil at the periphery only receives force from three or two sides of the coil, and the weight and weight of the suspension and edges are applied, so it is necessary to adjust the number of turns of the coil.

Figure 6 shows the voice coils lined up,
Since the voice coils are densely packed, the area of the diaphragm is equal to the area of the voice coil, and the weight of the diaphragm per voice coil is minimized.

Then, glue and fix the voice coils that were next to each other.

By doing so, the second moment of area of the vibrating portion increases, and the rigidity can be increased.

FIG. 7 is a sectional view of the driving portion, and this is a case where the diaphragm is flat.

FIG. 8 is also a sectional view of the vibrating part, and since the entire diaphragm is fixed by the voice coil, the diaphragm can be tilted at any location and at any angle.

In FIG. 9, this is made into a saw shape.

FIG. 10 shows the mounting position of the suspension that holds the vibrating part, and by mounting it on the center of gravity of the vibrating part, the vibrating part can be held by the suspension bracket.

In FIG. 11, an edge is added as in the conventional case in order to improve the precision of holding.

Figures 2 and 3 are for reference only, but since the space between the magnet and the diaphragm is surrounded by a voice coil, in order to reduce the negative effects of the spring action caused by air, a hole is made in the diaphragm as in the past. There is also a method of drilling holes, but in this case, the area of the hole is larger than the area of the imaging plate, so the hole is drilled in the magnet.

[Effects of the Invention] As described above, by arranging the magnets like the eyes of the base, the area of the diaphragm that is borne by one voice coil is the same as the cross-sectional area of the voice coil, so it is possible to improve the treble range. It is possible to reproduce the same level as the conventional Towiku, and it goes without saying that the larger the area of the diaphragm is ideal for bass, but the diameter of the diaphragm of the conventional model was limited to about 40 cm. On the other hand, with this speaker, there is no limit to the size of the diaphragm by arranging the magnets in succession.

Although there is no restriction on the area of the diaphragm, since the area of the diaphragm and the voice coil are the same, there is no part that causes split vibration.

In addition, since the entire diaphragm is fixed with a voice coil, the shape of the diaphragm can be changed freely, and the diaphragm is made flat to avoid the cavity effect that was a drawback of dynamic cone speakers. be able to.

In addition, since it is fully driven, there is no vibration transmitted from the center to the periphery like in the central drive system, and since the periphery is also fixed with a voice coil, there is no reflected vibration from the edges. Since there is no interference during imaging and there is no reflected vibration, the internal loss of the diaphragm, which was a major problem in the past, is no longer a problem.

However, since edges inevitably suppress vibration, it is better to have no edges if possible.

Regarding this point, in this speaker, the voice coils are closely fixed, so the vibrating part consisting of the diaphragm and voice coil has a very high rigidity, although it does not have a honeycomb structure. I will have
In addition to reducing the weight of the vibrating part, it is also possible to hold the vibrating part by simply attaching a suspension to the voice coil, eliminating the need to secure the diaphragm at the edges.

Regarding directivity, low-frequency sounds spread well, but as the frequency increases, the sound spread gets worse.

For this reason, the ideal shape is such that the surface of the diaphragm allows sound waves to spread in a spherical shape.

However, in conventional speakers, it has been impossible to fold the diaphragm midway in order to improve directivity due to problems with the rigidity of the diaphragm and the drive device.

However, in the case of the present invention, since the entire diaphragm is fixed by the voice coil, the diaphragm can be freely angled at any position to form a shape that allows sound waves to spread easily in a spherical shape.

In this way, most of the problems with conventional dynamic direct radiation speakers can be solved.In addition, since the magnetic field is created only with magnets and a large number of them are used, the size of the magnets can be small and the diaphragm can be large. However, the thickness of the speaker does not need to be increased that much, so it is possible to use the wall itself as a speaker, or the screen itself as a shooting board.

[Brief explanation of drawings]

Perspective view of the magnet Figure 2 and Figure 3 Perspective view of a magnet with air passages provided to reduce the spring action caused by air Figure 4 Layout of the magnet Figure 5 Perspective view of the voice coil (moving coil) Figure 6: Voice coil (moving coil) name 7: Cross-sectional view of the drive unit Figure 8/Figure 9: Cross-sectional view of the vibrating part Figures 10/11: Cross-sectional view of the support device for the vibrating part 1/ ...N pole 2...S pole 3...Base 4...Conductor 5...Voice coil (moving coil) 6...Diaphragm 7...Filling material to increase the rigidity of the vibrating part 8...
Magnet 9...Elan IO...Baffle plate 11...Suspension fixing base 12...Suspension fixing plate 13 for voice coil...Suspension

Claims (1)

[Claims] Magnets like the one shown in Figure 1 (square and U-shaped as shown in the figure seem to be optimal, but rod-shaped or U-shaped magnets can also be used) are arranged horizontally with N and S poles. If the two magnets face each other and the spacing between the magnets is the same as the spacing between the N and S poles of the magnets, the N and S poles will line up in a line at equal intervals. The spacing between each column is also the same as the spacing between the N and S poles. Then, when the left end of the first row is the N pole, the left end of the second row is the S pole, the third row starts from N, the fourth row starts from S, and so on, so that all the adjacent N poles are S. All adjacent poles and S poles become N poles. Also, a certain amount of space is secured around each pole into which the voice coil can be inserted. The magnets arranged in this way are arranged so as to cover the entire area of the diaphragm. Then, when the voice coil is wound right-handed around the N pole, the voice coil is wound left-handed around the S pole, each voice coil is directly connected to one diaphragm, and a sound current is passed through the voice coil. A speaker characterized by generating sound.