JP2009267779A - Electromagnetic electro-acoustic transducer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electromagnetic electro-acoustic transducer which has a configuration different from that of an electro-acoustic conversion means of a conventional speaker and can make the outer shape of a speaker sufficiently slender. <P>SOLUTION: In the electromagnetic electro-acoustic transducer, a magnetic body having a long shape longer than a long cylinder of a voice col is inserted into the voice coil wound in the shape of the long cylinder to form a vibrating member, and both ends of the magnetic body exposed out of the voice coil are held by dumpers to allow the vibrating member to vibrate in a direction perpendicular to the axis line thereof. Both ends of the vibrating member are held in magnetic gaps of a pair of magnetic circuits with magnetic field directions opposite to each other and are arranged in a longitudinal direction of the vibrating member so that they may vibrate. Vibration of the vibrating member generated by a magnetic field generated by voice signal application to the voice coil and a magnetic field in the magnetic gaps is transmitted to a diaphragm. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an electromagnetic electroacoustic transducer for a speaker mounted on a front panel or the like of a television receiver, and more particularly to an electromagnetic electroacoustic transducer suitable for use in a mounting space having a very limited size, particularly a small width. Related to the vessel.

  FIG. 9 shows a schematic diagram of the configuration of a conventional general speaker. In the figure, the magnetic circuit comprises an annular magnet 1, a disc-shaped yoke 2 having a cylindrical pole piece 3 in the center and a magnet 1 placed on the circumference, and a plate 4 placed on the magnet 1. A voice coil 5 wound around the outer periphery of one end of a cylindrical coil bobbin is inserted into a magnetic gap formed between the outer peripheral surface of the head of the pole piece 3 and the inner peripheral surface of the plate 4. The coil bobbin is held by the inner peripheral end of the annular damper 6 on the outer periphery of the other end, the outer peripheral end of the damper 6 is fixed to the inner peripheral part of the conical frame 7, and the coil bobbin carrying the voice coil 5 is In the axial direction, the magnetic gap is held so as to be able to vibrate. The other end edge of the coil bobbin is coupled to the inner peripheral end of the cone-type diaphragm 8, and the outer peripheral end of the diaphragm 8 is fixed to the outer peripheral portion of the frame 7 through the edge so as to vibrate. In this configuration, when a voice signal is applied to the voice coil 5, the voice coil 5 vibrates in the magnetic gap, and this vibration drives the diaphragm 6 to generate voice.

  In the speaker having the above configuration, in order to hold the cylindrical voice coil in the circular magnetic gap, it is necessary to surround the outer periphery of the voice coil 5 by a magnetic circuit in which the annular plate 4 and the magnet 1 are combined with the disc-shaped yoke 2. There is. Therefore, since the outer diameter of the speaker is defined by the dimensions of the magnetic circuit plate, magnet and yoke, it is impossible to reduce it beyond a certain limit.

For example, as seen in Patent Document 1, various speakers having an outer shape of an ellipse, an ellipse, a rectangle, etc. have been proposed in order to adapt to a narrow and narrow installation space, and a voice coil and a magnetic circuit are also elliptical. The size is reduced by following the external shape of the speaker in the form of a rectangle or a rectangle, but in any case there is no change in the configuration that surrounds the outer periphery of the voice coil with a magnetic circuit, so measures to change the external shape are also in the width direction of the special speaker It has not helped with a significant reduction in size. In addition, no attempt has been made to make the electroacoustic conversion means have an elongated outer shape with a configuration other than the shape in which the magnetic coil surrounds the voice coil.
Japanese Patent No. 3478466

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an electromagnetic electroacoustic transducer capable of making the external shape of a speaker sufficiently elongated with a configuration different from that of an electroacoustic transducer in a conventional speaker.

An electromagnetic electroacoustic transducer according to claim 1 is a vibration member made of a longitudinal cylindrical voice coil to which an audio signal is applied, a longitudinal magnetic body inserted into the voice coil along the axis of the voice coil, and a vibration member A damper that supports the magnet in the longitudinal direction so as to vibrate in a direction perpendicular to the longitudinal direction, a magnet that generates magnetic flux, and a pair of yokes that form a magnetic gap that concentrates the magnetic flux by connecting to the magnet. The vibrating member is supported by arranging both ends of the magnetic body in each magnetic gap of the pair of magnetic circuits.
The electromagnetic electroacoustic transducer according to claim 2 is characterized in that the vibration member collects the magnetic field generated in the voice coil when an audio signal is applied in the magnetic body and concentrates it on both ends in the longitudinal direction of the magnetic body.
The electromagnetic electroacoustic transducer according to claim 3 is characterized in that the magnetic circuits are arranged at both ends in the longitudinal direction of the magnetic body of the vibrating member, and the magnetic circuits are arranged so that the magnetic fields are reversed.
In the electromagnetic electroacoustic transducer according to claim 4, the magnetic body of the vibration member is formed by stacking two plate-like materials, and the damper is inserted between the two plate-like materials to support the vibration member. It is characterized by.
The electromagnetic electroacoustic transducer according to claim 5 is characterized in that the damper is a leaf spring.
The electromagnetic electroacoustic transducer according to claim 6 is characterized in that the damper maintains the end of the magnetic body at the center position in the magnetic gap.
The electromagnetic electroacoustic transducer according to claim 7 is a rectangular box-shaped frame having one of the long side surfaces as an opening, and a depth direction of the frame on the inner side that is fixed to both longitudinal ends of the frame and facing each other. Is a pair of magnetic circuits comprising a magnet and a yoke that form a magnetic gap that generates magnetic fields in opposite directions at the center of the magnet, and the magnet and the yoke are divided into two upper and lower parts along the central surface of the magnetic gap And a magnetic member generated by a voice signal applied to the voice coil, which is a vibrating member composed of two superposed plate-like magnetic bodies and a voice coil wound around a main portion other than both longitudinal end portions of the magnetic body. Are collected on the magnetic body so that both ends of the magnetic body are different from each other, and one end portion is sandwiched and fixed between the upper and lower portions of the magnetic circuit and the other end portion Characterized by comprising between the pair of dampers which can vibrate held in the depth direction of the frame between the two is of sandwiched between the magnetic body vibration member a pair of magnetic circuits of both end portions of the vibration member.

  The electromagnetic electroacoustic transducer according to the present invention forms a vibrating member by inserting a longitudinal magnetic body along the axis of a voice coil wound in a longitudinal cylinder, and forms both ends of the magnetic body exposed from the voice coil. Each of the vibration members can be vibrated in a direction perpendicular to the axial direction by being held in the longitudinal direction by the dampers, and the magnets of a pair of magnetic circuits in which both ends of the vibration members are disposed on both ends in the longitudinal direction of the vibration members, respectively. The structure is supported in the gap, and the vibration of the vibration member due to the magnetic field generated by the application of the audio signal to the voice coil and the magnetic field of the magnetic gap is extracted and transmitted to the diaphragm. Thus, the width dimension of the electromagnetic electroacoustic transducer can be remarkably reduced.

  In order to describe the present invention in more detail, embodiments shown in the attached drawings will be described.

  FIG. 1 shows an assembly of a voice coil 13 and a magnetic body 14 forming a vibrating member V in the electromagnetic electroacoustic transducer of Example 1 according to the present invention, and the voice coil 13 has a longitudinal cylindrical shape with a rectangular cross section. The magnetic body 14 is wound, and a longitudinal plate material used as, for example, an iron core is inserted into the cylindrical voice coil 13 along an axis in a two-layer stack here. Both end portions of the magnetic body 14 are exposed from both ends of the voice coil 13 by substantially the same length.

  2 is a longitudinal sectional view of the electromagnetic electroacoustic transducer 10 of Example 1 configured by combining the vibrating member V shown in FIG. 1 with a pair of magnetic circuits M, and FIG. 3 is a sectional view taken along line II-II in FIG. FIG. In the figure, the vibrating member V sandwiches one end portion of a pair of dampers 15 made of a plate-like elastic material such as a leaf spring between two magnetic bodies 14 at both end portions thereof. The end portion is sandwiched and fixed between two superposed thick plate-like magnets 11 in each of a pair of magnetic circuits M arranged at both ends of the vibration member V. Accordingly, the vibrating member V is held by a pair of magnetic circuits M positioned in the longitudinal direction of the vibrating member V so as to be able to vibrate in the thickness direction of the magnetic body 14 via the damper 15.

  In the magnetic circuit M, the upper and lower sides of the two stacked magnets 11 are sandwiched between the long legs of the two yokes 12 each having an L-shaped cross section, and the both ends of the magnetic body 14 of the vibrating member V are sandwiched between the short legs. By sandwiching and opposing each other, a magnetic gap G is formed between the tips of the short legs of the yoke 12, and both ends of the vibration member V are arranged at the center positions in the pair of magnetic gaps G positioned in the longitudinal direction. These pair of magnetic gaps G constitute each magnetic circuit M so that the directions of the magnetic fields are opposite to each other. Both magnetic circuits M are fixed to both ends of a rectangular box-shaped frame 18 whose one side surface in the longitudinal direction is open, and the vibration member V is elastically held via the damper 15 in the longitudinal direction.

  In the electromagnetic electroacoustic transducer 10 having the above-described configuration, when an electrical signal representing sound is applied to the voice coil 13, a magnetic field is generated in the voice coil 13, and the generated magnetic field is collected in the magnetic body 14. One end is magnetized to the N pole and the other end is magnetized to the S pole. In the mutual relationship between the polarities of both ends of the magnetic body 14 of the vibrating member V magnetized in this way and the polarities of the magnetic gaps G of both magnetic circuits M into which both ends of the magnetic body 14 are inserted, the vibrating member V The magnetic body 14 is driven in the thickness direction, that is, in the direction of the arrow y shown in FIG. 2A, and vibrates.

  Sound can be reproduced by transmitting the vibration of the vibration member V to a rectangular diaphragm (not shown) held on the opening side edge of the frame 18 via an edge, for example. However, the present invention provides a versatile electromagnetic electroacoustic transducer capable of transmitting to a diaphragm having another desired shape and size without limiting the reproduction frequency characteristic to the characteristic of a rectangular diaphragm.

  4 and 5 show an embodiment in which the electromagnetic electroacoustic transducer 10 according to the present invention adopts the above-described generality. In the figure, the electromagnetic electroacoustic transducer 10 has the same configuration and operation as those described above with reference to FIGS. 1 and 2 and is arranged in close proximity to the opening side surface of the frame 18. An adapter 17 is inserted between the plate 16 and the vibrating member V of the electromagnetic electroacoustic transducer 10 to drive the vibrating plate 16 by the vibration of the vibrating member V.

  The adapter 17 is formed in a table shape as seen in the longitudinal sectional view of FIG. 4 and in a substantially T shape in the transverse sectional view of FIG. 5 along the line III-III. A top plate joined to the rear surface of the diaphragm with a flat rectangular outer surface extending along the magnetic body, and a magnetic body exposed toward the opening of the frame 18 at both ends of the top plate in the longitudinal direction and both ends of the voice coil 13 of the vibration member V It consists of a pair of legs that connect between the 14 surfaces. Adhesion is maintained between the top plate and the diaphragm 16 and between the leg portion and the magnetic body 14. Further, the outer shape and dimensions of the diaphragm 16 are arbitrarily selected.

  FIG. 6 shows another specific embodiment of the electromagnetic electroacoustic transducer 10 of the present invention. Two electromagnetic electroacoustic transducers 10 are attached to the left and right ends of one panel-shaped diaphragm 16, respectively. By connecting to the left and right channel signal sources of stereo sound, stereo sound can be reproduced.

  FIG. 7 shows still another specific embodiment of the electromagnetic electroacoustic transducer 10 of the present invention, and two electromagnetic electroacoustic transducers 10 are used for stereo provided in the front of the television receiver 19. If it is embedded in the front panel frame while being attached to the left and right ends of the diaphragm 16, stereo sound reproduction can be performed as in the case of FIG. The television image can be displayed on the diaphragm 16. Further, the image display panel 20 can be used as a vibration plate in combination with the electromagnetic electroacoustic transducer of the present invention.

  FIG. 8 shows an electromagnetic electroacoustic transducer 10 according to a second embodiment of the present invention. In this case, in each of the pair of magnetic circuits M, the upper one of the upper and lower magnets 11 in the first embodiment is omitted, and the upper leg 12a of the upper yoke 12a is thickened accordingly. And the same magnetic field as the electromagnetic electroacoustic transducer 10 of Example 1 is comprised. According to the second embodiment, therefore, the same operation and effect can be obtained with higher economic efficiency than the first embodiment.

The perspective view which shows the vibration member which comprises the electromagnetic type electroacoustic transducer of this invention. The longitudinal cross-sectional view which shows the structure of the electromagnetic type electroacoustic transducer by this invention in Example 1 using the vibration member of FIG. FIG. 2B is a cross-sectional view of the electromagnetic electroacoustic transducer taken along line II-II in FIG. 2A. 1 is a longitudinal sectional view showing an embodiment of a diaphragm of an electromagnetic electroacoustic transducer of Example 1. FIG. FIG. 3B is a cross-sectional view of the electromagnetic electroacoustic transducer taken along line III-III in FIG. 3A. The perspective view of other embodiment which shows the combination with the diaphragm for stereo reproduction | regeneration of the electromagnetic type electroacoustic transducer of Example 1. FIG. The perspective view of further another embodiment which shows the stereo reproduction | regeneration structure in the television receiver of the electromagnetic type electroacoustic transducer of Example 1. FIG. FIG. 6 is a longitudinal sectional view showing a configuration of an electromagnetic electroacoustic transducer of the present invention in Example 2. Sectional drawing which shows the structure of the conventional speaker.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Electromagnetic type electroacoustic transducer 11 Magnet 12 Yoke 13 Voice coil 14 Magnetic body 15 Damper 16 Vibration plate 17 Adapter 18 Frame 19 Television receiver 20 Image display panel V Vibration member M Magnetic circuit G Magnetic gap

Claims (7)

  A longitudinal cylindrical voice coil to which an audio signal is applied, a vibration member made of a magnetic material having a longitudinal shape inserted through the voice coil along the axis of the voice coil, and the vibration member can vibrate in a direction perpendicular to the longitudinal direction. A damper for supporting in the longitudinal direction; a magnet for generating magnetic flux; and a pair of magnetic circuits each including a pair of yokes that form a magnetic gap for concentrating the magnetic flux connected to the magnet. An electromagnetic electroacoustic transducer characterized in that both ends are arranged and supported in each magnetic gap of a pair of magnetic circuits.   2. The electromagnetic electroacoustic transducer according to claim 1, wherein the vibration member collects a magnetic field generated in the voice coil when an audio signal is applied in the magnetic body and concentrates it on both ends in the longitudinal direction of the magnetic body.   2. The electromagnetic electroacoustic transducer according to claim 1, wherein the magnetic circuit is disposed at both longitudinal ends of the magnetic body of the vibrating member, and each magnetic circuit is disposed so as to reverse the magnetic field.   The magnetic body of the vibration member is formed by stacking two plate-like members, and the damper is inserted between the two plate-like members to support the vibration member. An electromagnetic electroacoustic transducer according to claim 1.   The electromagnetic electroacoustic transducer according to claim 4, wherein the damper is a leaf spring.   2. The electromagnetic electroacoustic transducer according to claim 1, wherein the damper maintains the end of the magnetic body at the center position in the magnetic gap.   A rectangular box-shaped frame with an opening in one of the longitudinal sides and a magnet that is fixed to both longitudinal ends of the frame and generates magnetic fields in opposite directions at the center in the depth direction of the frame inside each other. A pair of magnetic circuits consisting of a magnet and a yoke forming a gap, wherein the magnet and the yoke are divided into two upper and lower parts along the central surface of the magnetic gap, and two superposed long plate-like plates A vibrating member composed of a magnetic body and a voice coil wound around a main portion other than both longitudinal end portions of the magnetic body, so that a magnetic field generated by an audio signal applied to the voice coil has opposite polarities at both ends. Between the two magnetic bodies at both ends of the vibration member, and the other end is sandwiched between the upper and lower portions of the magnetic circuit and fixed. Electromagnetic transducer characterized by comprising in a pair of dampers which can vibrate held in the depth direction of the frame between clamped to the vibrating member of the pair with the magnetic circuit.

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