JP2007174171A - Inner magnet type speaker and magnet for inner magnet type speaker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inner magnet type speaker capable of obtaining high sound quality / high efficiency by using a magnet employing a spherical magnetic pole yoke. <P>SOLUTION: In the speaker comprising: a magnet comprising a center magnet, a center pole piece and a magnetic pole yoke; a frame body fitted to the magnetic pole yoke; a frame fitted to the frame body; a voice coil bobbin arranged movably to a magnetic gap between the center pole piece and the magnetic yoke and on which a voice coil is wound; a cone diaphragm coupled to the voice coil bobbin; and a damper arranged between the cone diaphragm and the frame, the magnetic pole yoke is configured with a spherical magnetic pole yoke whose cross-section is approximated to R curves along with magnetic lines of force in free air so as to avoid the presence of straight line parts in a magnetic path thereby suppressing leakage magnetic flux to 1% or below and supplying the maximum magnetic flux to the magnetic gap of sound reproduction resulting in that the speaker can develop excellent operating effects. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a speaker and a speaker magnet, and more specifically, an inner magnet employing a spherical structure that enables low input and high sound output by a combination of a magnet having a spherical magnetic pole yoke and a lightweight diaphragm. The present invention relates to a type speaker and an inner magnet type speaker magnet.

  Conventionally, as an audible frequency speaker, many improvements have been made to the configuration of magnets, diaphragms, etc. in order to increase the efficiency and fidelity of reproduced sound. Although there is no change in the structure to obtain the reproduced sound by causing the diaphragm to vibrate by passing an audio signal current through the voice coil connected to the diaphragm in the magnetic circuit used, high efficiency and high fidelity of the above reproduced sound In order to achieve the goal of making it easier, the development of better materials for each component of the speaker was one of the important issues.

  The most commonly used speaker for music playback, voice playback, etc. is a type that vibrates a cone-shaped diaphragm using a voice coil and a magnet employing a permanent magnet. In order to obtain a speaker capable of reproducing sound with high fidelity, a high magnetic flux density is required, and so far, much effort has been made to develop a strong permanent magnet capable of obtaining a high magnetic flux density. It was. However, in order to achieve the objectives of increasing the efficiency and fidelity of the reproduced sound, a speaker magnet that still has a sufficiently high magnetic flux density has not been realized.

  FIG. 1 shows an example of a moving coil type speaker using a conventional magnet. In this speaker device 100, an annular magnet 104 is disposed on an upper portion of a pole magnetic pole yoke 106, and an annular portion is disposed on the upper portion of the annular magnet 104. A plate 105 is disposed to form a magnetic circuit 107.

  In the magnetic gap 107a of the magnetic circuit 107, a voice coil 102 wound around the end of a voice coil bobbin 103 fixed to the central hole of the cone-shaped diaphragm 101 is disposed. Further, a cap 113 is provided in the central hole portion, and the outer peripheral portion of the cone-shaped diaphragm 101 is fixed to the outer peripheral portion of the frame 112 through the edge 108.

  Further, the central portion of the cone-shaped diaphragm 101 is supported by the frame 112 via a damper 109. Thereby, the cone-shaped diaphragm 101, the voice coil 102, and the voice coil bobbin 103 are integrated to vibrate in the direction of the central axis X of the speaker device 100.

  When the drive signal applied to the input terminal 110 provided on the frame 112 is supplied to the voice coil 102 via the lead wire 111, the voice coil 102 generates magnetic flux according to the drive signal, and the magnetic circuit An electromagnetic driving force is received by the interaction with the magnetic field of the magnetic gap 107a of the 107, whereby the cone-shaped vibrating body 101 vibrates in the direction of the central axis X of the speaker device 100, and sound corresponding to the input driving signal is reproduced. Is done.

  As a problem to be solved by the present invention, a high magnetic flux density that could not be obtained in the prior art is realized by adopting a spherical structure in the magnetic pole yoke and improving the magnetic path passing through the magnetic pole yoke. A small magnet with little leakage flux obtained by improving the magnetic pole yoke is applied to the speaker. In a conventional magnet for a speaker, the cross-sectional shape of the top plate and the cross-sectional shape of the side surface of the yoke are linear, the magnetic resistance deteriorates at the joined and bent portions, the leakage flux is relatively large, and the inner magnet type magnet is a so-called This is only possible with a pot-shaped yoke. Further, in the prior art, since the magnetic flux density is increased, an increase in the size of the magnet is inevitable, and various problems such as weight and volume have occurred during use.

  On the other hand, some of the early speakers used excitation type magnets were used in radio equipment, record players and other acoustic equipment, but with the development of powerful permanent magnets, most excitation type speakers have disappeared. It was. However, recently, in order to obtain a powerful speaker magnet without incurring enormous weight and volume, the excitation type magnet has been reviewed and a superconducting coil has been adopted as the excitation coil to obtain a high magnetic flux density. Speakers have also been developed.

  In the inner magnet type magnet according to the present invention, the cross sectional shape of the magnetic circuit is changed from the linear pot shaped yoke to the inner magnet type magnet in order to differentiate from the conventional pot shaped yoke. By changing to a spherical magnetic pole yoke with a curved line, considering that the magnetic resistance is low, and by configuring a natural and reasonable high-efficiency magnetic circuit that approximates the magnetic field lines of free air as an optimum shape It achieves a high magnetic flux density that could not be achieved with a speaker magnet that employs a permanent magnet and a pot-shaped magnetic pole yoke in the device. In the inner magnet type magnet of the present invention, the pole piece also has a circular shape. Like the shape of the spherical magnetic pole yoke, it is configured with a curved shape, and by eliminating the linear structure, a smooth line of magnetic force is created in the gap between the pole piece and the spherical magnetic pole yoke. It can be formed, and a structure capable of forming a maximum magnetic flux.

  The loudspeaker according to the present invention employs a spherical magnetic pole yoke as the magnetic pole yoke in order to obtain a strong magnetic flux density for achieving the objective without increasing the size of the inner magnet type magnet and magnetic pole yoke constituting the magnetic circuit. In addition to reducing the leakage flux as much as possible, the plate top plate, which is necessary for speaker magnets that employ permanent magnets and pot-shaped magnetic pole yokes with reduced magnetic resistance, is not present. The pressure efficiently escapes to the back (see arrow in FIG. 4 (B)), the back pressure air load is reduced with respect to the amplitude motion of cone paper, etc., and the freedom of amplitude motion is improved, thereby improving the compliance. Further, HiFi sound can be reproduced. The sound reproduced by the speaker according to the present invention is a high-resolution, highly transparent sound that has never been experienced before, and the sound reproduced by adopting an inner magnet type magnet using a spherical magnetic pole yoke is It stands out, and once it is listened to, the reproduced sound has a range that can never be forgotten.

  In addition to the improvement of the inner magnet type magnet, the present invention aims to reduce the weight of the vibration system by attaching a voice coil bobbin made of Gambi Japanese paper to the central hole part of a cone-shaped diaphragm made of hand-made Kozo Japanese paper having a substantially conical shape. By bringing the compliance of the vibration system close to the optimum state, it becomes possible to further improve the fidelity of the reproduced sound, and by combining this vibration system with the excitation type magnet of the present invention, it is more than expected. According to the present invention, for example, a single speaker having a diameter of 16.51 cm (6.5 inches) can be used to reproduce beyond the sound range of a conventional 2-way or 3-way speaker system. I was able to realize the sound.

  An embodiment according to the present invention will be described with reference to the drawings. 2 is a sectional view of a speaker according to the present invention, FIG. 3 is an exploded sectional view showing the structure of a spherical magnetic pole yoke, and FIG. 4 is a diagram showing the relationship between the spherical magnetic pole yoke of the present invention and free air magnetic field lines. 5 is an overall view of a speaker using the inner magnet type magnet of the present invention.

  In the speaker according to the present invention, a spherical magnetic pole yoke is disposed so as to surround a central structure composed of a central cylindrical magnet and a center pole piece on the magnet, and the magnetic pole yoke is disposed between the central pole piece and the spherical magnetic pole yoke. A magnetic circuit is configured by forming a gap.

  2A and 3, 1 is a magnet made of a permanent magnet or an exciting magnet, 2 is a center pole piece, 3 is a spherical magnetic pole yoke, 4 is a screw hole, and 13 is a frame directly attached to the spherical magnetic pole yoke. The base 5 is a magnetic gap between the spherical magnetic pole yoke and the center pole piece, 6 is a voice coil, 7 is a voice coil bobbin, 8 is a cone diaphragm coupled to the voice coil bobbin, and 9 is a damper.

  As shown in detail in FIG. 3, the spherical magnetic pole yoke, which is a feature of the present invention, is formed by joining two upper and lower semicircular magnetic pole yokes through alignment holes 18 and pins 19. A support screw 17 that extends from the lower spherical magnetic pole yoke through the mounting holes 15 and 15 provided in the upper spherical magnetic pole yoke, and is attached to the central magnet via the central mounting hole of the lower spherical magnetic yoke. 17 and nuts 16 and 16 and screws 14 and 14 penetrating the base 13 are firmly screwed to the base 13.

  In the present invention, by approximating the shape of the magnetic pole yoke to the magnetic field lines of free air coming out of the magnet 1, that is, the magnetic path of the magnetic pole yoke through which the magnetic flux from the magnet passes is changed to an R curve along the magnetic field lines of free air. By approximating, the magnetic part in the magnetic pole yoke eliminates the corner part consisting of the linear part, and the magnetic flux emitted from the magnet smoothly passes through the magnetic pole yoke. Was reduced to 1% or less as much as possible, so that all the magnetic flux passed through the magnetic gap, and the total magnetic flux energy could be increased in proportion to this, and an ideal inner magnet type magnet could be formed. . Although the embodiment using a permanent magnet as the inner magnet type magnet of the present invention has been described, it goes without saying that the same effect can be obtained even if an excitation type magnet is used (see FIG. 2B).

  In addition to the improvement of these internal magnet type magnets, in the present invention, a voice coil made of a thin square wire or a round copper wire is wound around the magnetic gap formed in the magnetic circuit of the internal magnet type magnet. For example, a voice coil bobbin formed of Gambi Japanese paper is positioned, and this voice coil bobbin is fixed to the central hole part of the cone-shaped diaphragm made of hand-made Kozo Japanese paper with a substantially conical shape to reduce the weight of the vibration system. It is possible to further improve the fidelity of the reproduced sound by bringing it close to the optimum state, and in addition, it was necessary for the speaker magnet that adopted the permanent magnet and pot-shaped magnetic pole yoke according to the prior art. Since the plate-shaped top plate does not intervene, the back pressure of the cone diaphragm efficiently escapes to the back (see the arrow in FIG. 4B), By back air load to oscillating motion of the over down paper or the like is improved flexibility of reduced amplitude motion, further improves compliance, it could occupy Sose sound reproduction effect than expected.

  It is possible to reproduce the full range of sound range by combining the handmade Japanese paper cone diaphragm of the present invention with a Gambi Japanese paper sub-cone and a dome-shaped cap made of pure gold, tin or aluminum thin plate. According to the present invention, the reproduction far exceeds the sound range of the conventional two-way and three-way speaker system in spite of a single speaker having a diameter of 16.51 cm (6.5 inches) as shown in FIG. Sound can be realized, and further, with the improvement of the efficiency of sound reproduction, the resolution becomes very good, and the good part and bad part of the amplifier power supply can be further distinguished, and as a result, the power supply of the amplifier itself The environment needs to be improved. As a result of viewing again after improving the power supply environment of the amplifier power supply, the speaker of the present invention resonated with a reproduced sound that was never experienced before, and the amount of musical sound information was impressive.

  In addition, the speaker of this invention is not limited to embodiment mentioned above, A suitable deformation | transformation, improvement, etc. are possible. For example, in the above-described embodiment, the cone-shaped speaker device has been described, but the present invention can be similarly applied to a dome-shaped speaker device.

Sectional drawing which shows the conventional speaker apparatus. It is sectional drawing of the speaker using the internal magnet type magnet concerning this invention, (A) is an example using a permanent magnet as an internal magnet type magnet, (B) is an example using an excitation type magnet. The exploded sectional view of the spherical magnetic pole yoke of the present invention. It is a figure which shows the relationship between the spherical magnetic pole yoke of this invention, and a free air magnetic field line, (A) is a figure which shows free air magnetic field line, (B) was approximated to R curve along the magnetic field line of free air. The figure which shows a spherical magnetic pole yoke. The whole figure of the speaker using the inner magnet type magnet of the present invention.

Explanation of symbols

1 magnet 2 pole piece
3 Spherical magnetic pole yoke 4 Mounting hole 5 Magnetic gap 6 Voice coil 7 Voice coil bobbin 8 Vibration plate 9 Damper 10 Frame (housing)
11 Subcone 12 Dome-shaped diaphragm (thin plate)
13 base

Claims (14)

A magnet comprising a magnet, a center pole piece and a magnetic pole yoke, a frame attached to the magnetic yoke, a frame attached to the frame, and a voice movably arranged in the magnetic gap between the center pole piece and the magnetic yoke In a speaker comprising a voice coil bobbin wound with a coil, a cone diaphragm coupled to the voice coil bobbin, and a damper disposed between the cone diaphragm and the frame,
An internal magnet type loudspeaker characterized in that the magnetic pole yoke is constituted by a spherical magnetic pole yoke approximated to an R curve along a magnetic field line of free air.   2. The internal magnet type speaker according to claim 1, wherein a voice coil bobbin around which the voice coil is wound and a cone diaphragm coupled to the voice coil bobbin are formed of Japanese paper.   3. The internal magnet type speaker according to claim 1, wherein a voice coil bobbin around which the voice coil is wound is made of Gambi Japanese paper, and a cone diaphragm coupled to the voice coil bobbin is made of Kozo Japanese paper.   3. An internal magnet type speaker according to claim 1, wherein a full-range sound range can be reproduced by combining a Japanese paper sub-cone and a dome-shaped diaphragm to the cone diaphragm.   5. The internal magnet type speaker according to claim 4, wherein the sub-cone is made of Kozo Japanese paper, and the dome-shaped diaphragm is made of a pure gold thin plate.   5. The internal magnet type speaker according to claim 4, wherein the dome-shaped diaphragm is formed of a thin tin plate.   5. The internal magnet type speaker according to claim 4, wherein the dome-shaped diaphragm is formed of an aluminum thin plate.   The internal magnet type speaker according to any one of claims 1 to 7, wherein the voice coil is formed by winding a square wire around a voice coil bobbin.   The internal magnet type speaker according to claim 1, wherein the magnet is a permanent magnet.   9. The internal magnet type speaker according to claim 1, wherein the magnet is an excitation type magnet. In the speaker magnet consisting of magnet, center pole piece, magnetic pole yoke and top plate,
An internal magnet type speaker magnet characterized in that the magnetic pole yoke is composed of a spherical magnetic pole yoke having an R curve along a free air magnetic force line.   The magnet for an internal magnet type speaker according to claim 11, wherein the spherical magnetic pole yoke is composed of a pole piece, an upper hemisphere portion, and a lower hemisphere portion.   The magnet for an internal magnet type speaker according to claim 11 or 12, wherein the magnet is a permanent magnet. 13. The internal magnet type speaker magnet according to claim 11, wherein the magnet is an excitation type magnet.

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