JP2008109288A - Speaker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a "speaker" suitable for thinning for securing satisfactory acoustic performance even in a middle and high sound area and a low sound area. <P>SOLUTION: A speaker 30 is configured to hold and fix a damper 38 between yokes 41 and 42 positioned at the outside of a diameter direction of magnetic gaps G1 and G2, and elastically support a bobbin 32 at the internal peripheral part of the damper 38, and to elastically support a diaphragm 35 at the outer peripheral part of the damper 38. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an electrodynamic loudspeaker, and more particularly, to a loudspeaker having a tapered diaphragm disposed so as to surround a bobbin around which a voice coil is wound.

  Conventionally, there is a configuration in which the diaphragm is disposed around the bobbin by fixing the base end of the bobbin to the inner peripheral edge with a small diameter with the large diameter side of the tapered diaphragm facing the magnetic circuit side, Therefore, there is known a speaker that is reduced in thickness by suppressing the overall height dimension. In this type of speaker, the damper that elastically supports the vibration system is bonded and fixed to the bobbin (for example, see Patent Document 1), and the damper is bonded and fixed to the outer peripheral portion of the diaphragm (for example, Patent Document 2). See).

  FIG. 7 is a cross-sectional view of a speaker showing the former conventional example disclosed in Patent Document 1. This speaker 1 is wound around a magnetic circuit 2 having a magnetic gap G and a tip portion of a bobbin 3 so as to be magnetic gap. A voice coil 4 disposed in G, a diaphragm 5 made of cone paper or the like formed in a taper shape, and having an inner peripheral edge bonded and fixed to a base end portion (upper end portion in the drawing) of the bobbin 3, and a magnetic circuit 2 And the lower frame 7 and the upper frame 8 that support the outer peripheral edge of the diaphragm 5 via the edge 6, and the outer peripheral edge is held and fixed to the upper frame 8 and the inner peripheral edge is the bobbin. 3 is provided with a damper 9 adhered and fixed to the base end of 3, a dust cap 10 attached to the bobbin 3, and a dust screen 11 covering the opening 7 a of the lower frame 7. The magnetic circuit 2 includes a magnet 12 and yokes 13 and 14, and a magnetic gap G is formed between the yokes 13 and 14.

  The speaker 1 configured in this way is arranged so that the diaphragm 5 surrounds the bobbin 3 by directing the large diameter side of the tapered diaphragm 5 toward the magnetic circuit 2 side. Thinning with reduced height is realized. The damper 9 of the speaker 1 is disposed so as to cover the opening 8 a of the upper frame 8, and elastically supports the base end of the bobbin 3 and the inner peripheral edge of the diaphragm 5.

  On the other hand, FIG. 8 is a cross-sectional view of a speaker showing the latter conventional example disclosed in Patent Document 2, and portions corresponding to those in FIG. In the speaker 20 shown in FIG. 8, an annular spacer 16 is provided on the inner wall portion 15 a of the frame 15 where the magnetic circuit 2 is installed, and outer peripheral edge portions of a pair of dampers 17 and 18 held and fixed to the annular spacer 16. Is bonded and fixed to the outer peripheral edge of the diaphragm 5. In this way, if the outer peripheral edge of the diaphragm 5 is supported by the plurality of dampers 17 and 18 to increase the restraining force on the vibration system, an undesirable rolling phenomenon can be caused even if the bobbin 3 is not directly supported by the damper. Can be suppressed.

The magnetic circuit 2 of the speaker 20 is constituted by a substantially cylindrical laminated body in which a magnet 21 is interposed between a lower yoke 22 and an upper yoke 23, and an annular yoke 24 surrounding the laminated body. Yes. A magnetic gap G1 is formed between the lower yoke 22 and the annular yoke 24, and a magnetic gap G2 is formed between the upper yoke 23 and the annular yoke 24. Each magnetic gap G1, G2 Voice coils 25 and 26 wound around the bobbin 3 are arranged. That is, the magnetic circuit 2 of the speaker 1 shown in FIG. 7 has a one-gap structure, but the magnetic circuit 2 of the speaker 20 shown in FIG. 8 has a two-gap structure.
JP-A-8-237794 (page 3-4, FIG. 4) Japanese Patent Laying-Open No. 2006-41676 (page 4-7, FIG. 1)

  By the way, in the former conventional example shown in FIG. 7, the speaker 1 can be used regardless of whether the front direction of the speaker 1 is the upper side or the lower side of the drawing. 9 and the upper frame 8 are likely to be an acoustic obstacle, and when the front direction is the lower side in the figure, the magnetic circuit 2 and the dust screen 11 are likely to be an acoustic obstacle. For this reason, the conventional speaker 1 has a problem in that the frequency characteristics are disturbed and the directivity characteristics are liable to be deteriorated in the mid-high range, and good acoustic performance cannot be expected. If the dust-proof screen 11 is removed from the speaker 1, foreign matter enters the magnetic gap G from the outside and malfunctions easily.

  On the other hand, in the case of the latter conventional example shown in FIG. 8, if the front direction of the speaker 20 is used as the upper side in the drawing, there is no acoustic obstacle in front of the diaphragm 5, so that the acoustic performance in the mid-high range is not deteriorated. However, in order to suppress the rolling phenomenon of the bobbin 3, it is necessary to increase the restraining force on the vibration system by using a plurality of dampers 17 and 18, and thus another problem that a sufficient amount of amplitude cannot be secured in the vibration system. was there. That is, since the damper mechanism of the speaker 20 elastically supports the outer peripheral edge of the diaphragm 5 that is far away from the bobbin 3, if the restraining force on the vibration system is weak, the bobbin 3 rolls at the time of high input and generates abnormal noise. There is a risk that the voice coil 4 may break off or cause a disconnection accident of the voice coil 4. Therefore, in the conventional speaker 20, it is necessary to employ a damper mechanism that increases the restraining force on the vibration system. As a result, the amplitude amount of the vibration system is suppressed, so that good acoustic performance can be secured in the low frequency range. It will disappear.

  The present invention has been made in view of such a situation of the prior art, and an object of the present invention is to provide a speaker suitable for thinning, which can ensure good acoustic performance even in a mid-high range and a low range.

  In the present invention, a damper is held and fixed to a yoke located radially outside the magnetic gap, and the bobbin and the diaphragm are elastically supported by the damper. In that case, the configuration may be such that the inner peripheral portion of one damper elastically supports the bobbin and the outer peripheral portion elastically supports the diaphragm, or the bobbin is elastically supported by a damper provided on the radially inner side of the yoke. In addition, the diaphragm may be elastically supported by another damper provided on the outer side in the radial direction of the yoke.

  According to the speaker of the present invention, since both the bobbin and the diaphragm are elastically supported by the damper, the bobbin rolling phenomenon is suppressed even at high input, and a sufficient amount of amplitude can be secured in the vibration system. Therefore, good acoustic performance can be secured in the low sound range. In addition, this speaker can be configured such that the diaphragm is greatly exposed in the front direction and there is no acoustic obstacle in the front, and therefore, good acoustic performance can be ensured even in the mid-high range. And this speaker is suitable for thickness reduction since the taper-shaped diaphragm is arrange | positioned so that a bobbin may be surrounded.

  The present invention includes a bobbin around which a voice coil is wound, a magnetic circuit having a magnetic gap in which the voice coil is disposed, a taper shape disposed radially outward of the bobbin, and an inner peripheral edge of the bobbin. In a speaker that includes a diaphragm that supports an end portion and a frame that is integrated with the magnetic circuit and supports an outer peripheral edge of the diaphragm, and the diaphragm is driven by energizing the voice coil. A damper is held and fixed to a yoke located radially outside the magnetic gap in the magnetic circuit, and an inner peripheral edge portion of the damper extending radially inward from the yoke is fixed to the bobbin. The portion of the damper that extends radially outward from the yoke is fixed to the diaphragm.

  In the speaker configured in this way, since the bobbin and the diaphragm are both elastically supported by the damper, the bobbin rolling phenomenon is suppressed even at high input, and a sufficient amount of amplitude can be secured in the vibration system. Therefore, good acoustic performance can be secured in the low sound range. In addition, this speaker can be configured such that the diaphragm is greatly exposed in the front direction and there is no acoustic obstacle in the front, and therefore, good acoustic performance can be ensured even in the mid-high range.

  In the above configuration, the damper fixed to the diaphragm is extended outward in the radial direction of the diaphragm and fixed to the frame so that the diaphragm is supported by the frame via the extension portion of the damper. In this case, in an ordinary speaker, an edge portion interposed between the frame and the outer peripheral edge portion of the diaphragm can be omitted, so that the component cost can be reduced.

  Further, in the above configuration, a groove serving as an adhesive reservoir is formed at the outer peripheral edge of the damper fixed to the diaphragm, and a portion of the damper adjacent to the groove is bonded and fixed to the diaphragm. Then, there is no possibility that the adhesive flows down along the tapered diaphragm, and the relative position between the damper and the diaphragm can be defined with high accuracy using the groove-shaped adhesive reservoir as a positioning portion.

  Further, in the above configuration, the yoke holding and fixing the damper has a first yoke and a second yoke sandwiching the damper, and the first yoke and the second yoke are along the circumferential direction. When the concave / convex fitting is performed at a plurality of locations, not only the magnetic efficiency of the yoke is improved, but also the damper can be easily attached to the yoke with high positional accuracy using the fitting convex portion of the first yoke or the second yoke. Can do.

  An embodiment will be described with reference to the drawings. FIG. 1 is a cross-sectional view of a speaker according to a first embodiment of the present invention, and FIG. 2 is an enlarged view of a portion A in FIG.

  The speaker 30 shown in FIG. 1 includes a magnetic circuit 31 in which magnetic gaps G1 and G2 are arranged in parallel at a predetermined interval, and a pair of coils wound around a bobbin 32 and disposed in the magnetic gaps G1 and G2. The magnetic coil 31 is integrated with the voice circuit 33, 34, the diaphragm 35 made of cone paper formed in a taper shape, and the inner peripheral edge thereof being bonded and fixed to the base end portion (upper end portion in the drawing) of the bobbin 32. The bobbin 32 and the diaphragm 35 are held and fixed between the frame 37 supporting the outer peripheral edge of the diaphragm 35 via the edge 36 and the cylindrical yoke 41 and the tapered yoke 42 of the magnetic circuit 31, respectively. The damper 38 that is elastically supported and the dust cap 39 that is attached to the bobbin 32 are mainly configured. Since the speaker 30 is disposed so that the tapered diaphragm 35 surrounds the magnetic circuit 31 and the bobbin 32, the speaker 30 is thinned with the overall height suppressed.

  The magnetic circuit 31 includes a substantially cylindrical laminated body in which a magnet 40 is interposed between a lower yoke 43 and an upper yoke 44, an annular plate yoke 45 surrounding the lower yoke 43 via a magnetic gap G1, The cylindrical yoke 41 is provided upright on the outer peripheral portion of the ring-shaped plate yoke 45, and the tapered yoke 42 surrounds the upper yoke 44 via the magnetic gap G2. The magnet 40 is magnetized in the axial direction, and each yoke 41 to 45 is made of a magnetic material such as iron. The frame 37 on which the lower yoke 43 and the ring-shaped plate yoke 45 of the magnetic circuit 31 are placed and fixed is made of a nonmagnetic material such as an aluminum alloy.

  In the magnetic circuit 31, the annular plate-like yoke 45, the cylindrical yoke 41, and the tapered yoke 42 located radially outside the magnetic gaps G1 and G2 form a magnetic path from the magnetic gap G1 to the magnetic gap G2. So as to be integrated. Although the cylindrical yoke 41 and the ring-shaped plate yoke 45 are bonded and fixed to each other, the both 41 and 45 may be integrated. As shown in FIG. 2, convex portions 41 a are projected at a plurality of locations along the circumferential direction on the upper end surface of the cylindrical yoke 41, and the convex portions 41 a are cut on the lower end surface of the tapered yoke 42. The cylindrical yoke 41 and the tapered yoke 42 are concavo-convexly fitted with the damper 38 interposed therebetween by being fitted into the provided recess. Engagement holes 38a for inserting the protrusions 41a are formed at a plurality of locations along the circumferential direction of the damper 38.

  The inner peripheral edge of the damper 38 is bonded and fixed to the middle of the two portions of the outer peripheral surface of the bobbin 32 around which the voice coils 33 and 34 are wound. That is, the bobbin 32 is not only supported at the base end portion (the upper end portion in the figure) by the vibration plate 35, but the circumferential portion located in the middle between the winding portions of the voice coils 33 and 34 is elastically supported by the damper 38. Has been. On the other hand, the outer peripheral edge portion of the damper 38 is bonded and fixed in the vicinity of the outer peripheral edge portion of the diaphragm 35 supported by the edge portion 36, and the outer peripheral edge portion of the diaphragm 35 is elastically supported by the damper 38. Engagement holes 38a are formed at a plurality of locations in the radial intermediate portion of the damper 38, and the peripheral portion of the engagement hole 38a is sandwiched between a cylindrical yoke 41 and a tapered yoke 42 as shown in FIG. It is worn. In addition, since the engaging hole 38a and the convex portion 41a of the cylindrical yoke 41 have substantially the same width in the radial direction, the convex portion 41a is inserted into the engaging hole 38a during assembly work. The damper 38 can be positioned with respect to the cylindrical yoke 41. As shown in FIG. 1, the posture of the damper 38 when no vibration is applied to the vibration system is set along a plane orthogonal to the axial direction.

  The speaker 30 configured in this way is used with the upper side in the figure as the front direction, and a voice current is supplied to the voice coils 33 and 34 via lead wires (not shown). That is, when an audio current is applied, electromagnetic force acts on the voice coils 33 and 34 in the magnetic gaps G1 and G2 to vibrate the bobbin 32. Therefore, the diaphragm 35 is driven to vibrate and sound is output.

  In this speaker 30, since both the bobbin 32 and the diaphragm 35 are elastically supported by the damper 38, the rolling phenomenon of the bobbin 32 is suppressed even at a high input, and a sufficient amount of amplitude can be secured in the vibration system. Therefore, good acoustic performance can be secured in the low sound range. In addition, the speaker 30 has a configuration in which the diaphragm 35 is largely exposed in the front direction and no acoustic obstacle exists in the front, and therefore, good acoustic performance can be ensured even in the mid-high range.

  In this embodiment, the inner peripheral portion of one damper 38 elastically supports the bobbin 32 and the outer peripheral portion of the damper 38 elastically supports the vibration plate 35. However, the sizes are different. Using two dampers, the outer peripheral edge of one small-diameter damper and the inner peripheral edge of the other large-diameter second damper are sandwiched between the yokes 41 and 42, and the inner peripheral edge of the small-diameter damper The outer peripheral edge of a large-diameter damper may be bonded and fixed to the diaphragm 35 by bonding and fixing to the bobbin 32.

  FIG. 3 is a cross-sectional view of a speaker according to a second embodiment of the present invention. Parts corresponding to those in FIG.

  The speaker 50 shown in FIG. 2 has a configuration in which the damper 38 is extended outward in the radial direction of the diaphragm 35 and fixed to the frame 37, and the diaphragm 35 is supported by the frame 37 through the extended portion 38b. This is different from the speaker 30 of the first embodiment described above. Therefore, this speaker 50 has an advantage that the edge portion interposed between the frame and the outer peripheral edge portion of the diaphragm in a general speaker can be omitted, and the cost of components can be reduced. In addition, when the diaphragm 35 is supported by the same member (damper 38) in this way, stress is less likely to act on the diaphragm 35 even if the temperature and humidity change, so that the acoustic performance is stabilized. is there. In the second embodiment, two dampers having different sizes may be used, and the bobbin 32 may be elastically supported by a small diameter damper, and the diaphragm 35 may be elastically supported by a large diameter damper.

  4 is a cross-sectional view of a speaker according to a third embodiment of the present invention, and FIG. 5 is an enlarged view of a portion B in FIG. 4. The same reference numerals are given to the portions corresponding to those in FIG. To do.

  In the speaker 60 shown in FIGS. 4 and 5, a groove portion 38 c serving as an adhesive reservoir is formed at the outer peripheral edge portion of the damper 38. The portion adjacent to the groove 38c at the outer peripheral edge of the damper 38 is bonded and fixed to the outer peripheral edge of the diaphragm 35, and the edge portion 36 supports the diaphragm 35 slightly ahead of the damper 38. This is different from the speaker 30 of the first embodiment described above. Therefore, the speaker 60 can reduce the diameter of the frame 37 even if the stroke of the vibration system is the same as in the first embodiment. Further, the speaker 60 has an advantage that it can be adapted to various frames having different calibers because the attachment position of the edge portion 36 with respect to the diaphragm 35 can be appropriately selected. Further, since the speaker 60 has the groove portion 38c serving as an adhesive reservoir, there is no possibility that the adhesive flows down along the tapered vibration plate 35, and the relative position between the damper 38 and the vibration plate 35 is determined by using the groove portion 38c as a positioning portion. This has the advantage that the position can be defined with high accuracy. In the third embodiment, two dampers having different sizes may be used, and the bobbin 32 may be elastically supported by a small-diameter damper and the diaphragm 35 may be elastically supported by a large-diameter damper.

  FIG. 6 is a cross-sectional view of a loudspeaker according to a fourth embodiment of the present invention. Parts corresponding to those in FIG.

  The speaker 70 shown in FIG. 6 has an edge attached to the spacer 70 while fixing the spacers 70 and 71 on the upper yoke 44 of the magnetic circuit 31 by removing the dust cap 39 in the first embodiment (speaker 30) described above. The portion 72 is configured to support the inner peripheral edge of the diaphragm 35, and a screw hole 71 a is formed in the central portion of the spacer 71. The speaker 70 can be easily fastened and fixed to the speaker grille 80 by screwing a fixing screw 81 passed through the speaker grille 80 disposed on the front surface into the screw hole 71a of the spacer 71. However, an elastic member 82 such as a sponge is preferably interposed between the outer periphery of the frame 37 and the speaker grill 80.

  In each of the above-described embodiments, the magnetic circuit having the two-gap structure in which the magnetic gap G1 in which the voice coil 33 is disposed and the magnetic gap G2 in which the voice coil 34 is disposed is described. In this case, it goes without saying that the same effect as described above can be obtained by elastically supporting the bobbin 32 and the diaphragm 35 with dampers.

It is sectional drawing of the speaker which concerns on 1st Example of this invention. It is the A section enlarged view of FIG. It is sectional drawing of the speaker which concerns on 2nd Example of this invention. It is sectional drawing of the speaker which concerns on 3rd Example of this invention. It is the B section enlarged view of FIG. It is sectional drawing of the speaker which concerns on 4th Example of this invention. It is sectional drawing of the speaker which concerns on a prior art example. It is sectional drawing of the speaker which concerns on another prior art example.

Explanation of symbols

30, 50, 60, 70 Speaker 31 Magnetic circuit 32 Bobbin 33, 34 Voice coil 35 Diaphragm 36 Edge portion 37 Frame 38 Damper 38a Engagement hole 38b Extension portion 38c Groove portion 39 Dust-proof cap 40 Magnet 41 Cylindrical yoke (first yoke yoke)
41a Convex part 42 Tapered yoke (second yoke)
70, 71 Spacer 80 Speaker grill 81 Fixing screw G1, G2 Magnetic gap

Claims (4)

A bobbin around which a voice coil is wound, a magnetic circuit having a magnetic gap in which the voice coil is disposed, and a taper shape disposed radially outward of the bobbin so that an inner peripheral edge supports the base end of the bobbin A speaker that is integrated with the magnetic circuit and supports an outer peripheral edge of the diaphragm, and the diaphragm is driven by energizing the voice coil.
A damper is held and fixed to a yoke located radially outside the magnetic gap in the magnetic circuit, and an inner peripheral edge portion of the damper extending radially inward from the yoke is fixed to the bobbin. A speaker is characterized in that a portion of the damper that extends radially outward from the yoke is fixed to the diaphragm.   2. The diaphragm according to claim 1, wherein the diaphragm fixed to the diaphragm is extended outward in the radial direction of the diaphragm and fixed to the frame, whereby the diaphragm is interposed through the extension portion of the damper. A speaker supported by the frame.   The groove portion serving as an adhesive reservoir is formed in an outer peripheral edge portion of the damper fixed to the diaphragm, and a portion of the damper adjacent to the groove portion is formed on the diaphragm. A speaker characterized by being bonded and fixed.   4. The method according to claim 1, wherein the yoke includes a first yoke and a second yoke sandwiching the damper, and the first yoke and the second yoke are provided at a plurality of locations along the circumferential direction. The speaker is characterized by having a concave and convex fitting.

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