JP2005039647A - Electromagnetically coupled speaker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electromagnetically coupled speaker capable of guiding magnetic fluxes more than generated by a woofer voice coil to an induction coil and improving the efficiency of a speaker for a tweeter. <P>SOLUTION: In this composite type electromagnetically coupled speaker, a cutting part 17 is provided on the outer circumference of a yoke pole 11 close to the inner side of the wafer voice coil 15 and the induction coil 16 is wound around. Also, the induction coil 16 is formed by winding magnetic metal wiring around the cutting part 17 so as to prevent a decrease in a magnetic flux in a magnetic gap G of a magnetic circuit by providing the cutting part 17. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an electromagnetically coupled speaker.

  A conventional composite electromagnetic coupling speaker is configured as shown in FIG. 3, for example. The electromagnetically coupled speaker shown in FIG. 3 includes a woofer voice coil 3 disposed in a magnetic gap G formed between a central hole of a top plate 1 constituting a magnetic circuit and a yoke pole 2, and the woofer voice coil. 3, a cone-shaped diaphragm 4 added to 3, an induction coil 5 for electromagnetic coupling disposed in a magnetic field generated in the woofer voice coil 3, and a bimorph type or a unimorph type driven by an induction voltage of the induction coil The tweeter piezoelectric speaker 6 is composed of a piezoelectric element.

  In addition, in the electromagnetically coupled speaker shown in FIG. 3, the induction coil 5 is formed by winding a copper wire around the convex portion 2 a provided on the upper surface of the yoke pole 2. The induction coil 5 formed in this way is disposed so as to be located in a magnetic field generated by an alternating current flowing through the woofer voice coil 3.

Furthermore, as the arrangement position of the induction coil, for example, the induction coil is arranged on the outer peripheral surface of the support supporting the piezoelectric speaker for tweeter fixed on the upper surface side of the magnet constituting the magnetic circuit, and the induction voltage from the induction coil is used as the piezoelectric speaker for tweeter There has been proposed a configuration in which the terminals are electrically connected so as to be supplied. (For example, see Patent Document 1)
Japanese Patent Laid-Open No. 9-18993 (page 2-3, FIG. 1)

  In the conventional composite type electromagnetically coupled speaker, the induction coil for obtaining the induced voltage for driving the piezoelectric speaker for tweeter is arranged at a position relatively distant from the voice coil for woofer. The magnetic flux generated from the voice coil cannot be used effectively, and a sufficient induced voltage cannot be obtained.

  The present invention has been made in view of such problems of the prior art, and the object of the present invention is to induce more magnetic flux generated by the woofer voice coil to the induction coil. Therefore, an electromagnetically coupled speaker capable of improving the efficiency of a tweeter speaker is provided.

  In order to achieve the above object, an electromagnetically coupled speaker according to the present invention includes a woofer voice coil disposed in a magnetic gap formed between a center hole of a top plate constituting a magnetic circuit and a yoke pole, and a woofer. Combined electromagnetic coupling type comprising a diaphragm added to a voice coil for induction, an induction coil for magnetic coupling arranged in a magnetic field generated in the voice coil for woofer, and a tweeter speaker driven by the induction voltage of the induction coil In the speaker, a cutting portion is provided on the outer periphery of the yoke pole near the inside of the woofer voice coil, and an induction coil is wound around the cutting portion.

  The electromagnetically coupled speaker according to the present invention is added to the woofer voice coil and the woofer voice coil disposed in the magnetic gap formed between the center hole of the top plate constituting the magnetic circuit and the yoke pole. A composite electromagnetically coupled speaker comprising a diaphragm, an induction coil for magnetic coupling arranged in a magnetic field generated in a woofer voice coil, and a tweeter speaker driven by an induction voltage of the induction coil. A cutting part is provided on the outer periphery of the upper end, and the cutting part is formed so that the lower end of the induction coil is positioned higher than the upper end of the woofer voice coil at the maximum amplitude of the woofer voice coil. It is configured.

  Furthermore, the electromagnetically coupled speaker of the present invention is added to the woofer voice coil and the woofer voice coil disposed in the magnetic gap formed between the center hole of the top plate constituting the magnetic circuit and the yoke pole. A composite electromagnetically coupled speaker comprising a diaphragm, an induction coil for magnetic coupling arranged in a magnetic field generated in a woofer voice coil, and a tweeter speaker driven by an induction voltage of the induction coil. Cutting portions are provided at positions on the outer periphery that are vertically divided with respect to the top plate, the induction coil is wound around the upper cutting portion, and the groove depth of the lower cutting portion is set to the groove depth of the upper cutting portion. The unbalance of the magnetic flux flow generated by providing the upper cutting part and the shallower part of the upper part is separated by the lower cutting part. One in which was configured to nest.

  In addition, it is effective that the induction coil is formed by winding a magnetic metal wire around a cutting part to prevent a decrease in magnetic flux in the magnetic gap of the magnetic circuit due to the provision of the cutting part.

  The electromagnetically coupled speaker according to the present invention can induce more magnetic flux generated by the woofer voice coil to the induction coil, and can greatly improve the efficiency of the tweeter speaker.

  In a composite electromagnetic coupling type speaker, a cutting part is provided on the outer periphery of a yoke pole near the inside of the woofer voice coil, and an induction coil is wound around the cutting part. In addition, the induction coil is formed by winding a magnetic metal wire around a cutting part to prevent a decrease in magnetic flux in the magnetic gap of the magnetic circuit due to the provision of the cutting part.

A first embodiment of an electromagnetically coupled speaker according to the present invention will be described with reference to a cross-sectional view of the main configuration shown in FIG.
In FIG. 1, reference numeral 10 denotes a disk-shaped yoke, which is provided with a yoke pole 11 formed by being planted or integrated at the center position. A magnet 12 such as a ferrite formed in a ring shape around the yoke pole 11 is disposed along the outer periphery of the yoke 10 on the disk and fixed to the upper surface of the yoke 10.

  Further, on the upper surface of the magnet 12, a top plate 13 on a disk made of a plate material such as pure iron having a central hole formed in the center is fixed concentrically with the yoke pole 11. A ring-shaped magnetic gap G is formed between the inner periphery of the center hole of the top plate 13 and the outer periphery of the yoke pole 11. A woofer voice coil 15 wound around the lower end of the coil bobbin 14 is inserted into the magnetic gap G.

  Although not shown in FIG. 1, a funnel-shaped metal frame is fixed near the outer periphery of the upper surface of the top plate 13, and further, between the upper end outer periphery of the coil bobbin 14 and the outer periphery of the opening of the metal frame. A funnel-shaped diaphragm having an edge is provided to constitute a woofer speaker. A tweeter piezoelectric speaker composed of a bimorph type or unimorph type piezoelectric element is disposed on a support provided on the upper surface of the yoke pole 11 to constitute a composite electromagnetic coupling type speaker.

  As shown in FIG. 1, the induction coil 16 for supplying an induction voltage to the tweeter piezoelectric speaker is provided with a cutting portion 17 on the outer periphery of the yoke pole 11 near the inside of the woofer voice coil 15, and the cutting portion 17 is connected to the cutting portion 17. It is formed by winding a magnetic metal wire such as an iron wire in a coil shape. Thus, by providing the induction coil 16 at a position close to the woofer voice coil 15, more magnetic flux generated in the woofer voice coil 15 can be reliably induced to the induction coil 16, and an increase in induction voltage can be achieved. It becomes possible to plan. The induced voltage obtained by the induction coil 16 is supplied to the tweeter piezoelectric speaker through the lead wire 18.

  In addition, the induction coil 16 formed by being wound around the cutting portion 17 uses a magnetic metal wire such as an iron wire as described above, instead of a commonly used copper wire. Thus, by using a magnetic metal wire as the wire forming the induction coil 16, it is possible to prevent a decrease in magnetic flux in the magnetic gap G due to the cutting portion 17 provided on the yoke pole 11.

  That is, in the case of a commonly used copper wire, the magnetic gap G is apparently widened and the magnetic flux is reduced. However, by using a magnetic metal wire made of the same material as the yoke pole 11, the cutting portion It is possible to maintain a state close to a structure in which 17 is not provided, to drive the woofer voice coil 15 in the axial direction (vertical direction in the figure), and to a magnetic field generated in the woofer voice coil based on this drive operation. The influence of can be reduced.

  Next, a second embodiment of the magnetically coupled speaker according to the present invention will be described with reference to a cross-sectional view of the main configuration shown in FIG. The same parts as those in the first embodiment of FIG. 1 are denoted by the same reference numerals, and detailed description of common parts is omitted since it is duplicated.

  The magnetically coupled speaker shown in FIG. 2A is an extended pole with the yoke pole 11 extended upward, and a cutting portion 19 is provided on the outer periphery of the yoke pole 11 above the top plate 13. The induction coil 16 is arranged by winding a wire in a coil shape. By adopting such a structure, as in the first embodiment shown in FIG. 1, compared to the case where the cutting portion 17 is provided on the outer periphery of the yoke pole 11 near the inside of the woofer voice coil 15, apparently, The magnetic gap G can be formed narrow.

  In the case of the second embodiment, the position where the cutting portion 19 is provided is limited. In particular, the cutting portion 19 is provided so that the lower end position of the induction coil 16 is positioned higher than the upper end position of the woofer voice coil 15 at the maximum amplitude of the woofer voice coil 15. Yes.

  Specifically, assuming that the thickness of the top plate 13 is t, a notched cutting portion 19 is formed on the upper side from a position of 0.75 t from the center of the thickness t of the top plate 13. Forming the cutting part 19 from the position of 0.75 t means that the lower end position of the induction coil 16 is higher than the upper end of the top plate 13 by 0.25 t. In consideration of the maximum amplitude of the woofer voice coil 15, the cutting portion 19 for winding the induction coil 16 is configured not to cover the amplitude range of the woofer voice coil 15.

  When the cutting part 19 is provided at a position corresponding to the amplitude range of the woofer voice coil 15, the magnetic gap G of the woofer voice coil 15 is substantially widened, resulting in a reduction in efficiency. On the other hand, if the lower end position of the cutting part 19 is made larger than the position of 0.75 t, the induction voltage by the induction coil 16 cannot be obtained sufficiently.

  Accordingly, the lower end position of the induction coil 16 is positioned higher than the upper end position of the woofer voice coil 15 at the maximum amplitude of the woofer voice coil 15 as in the second embodiment. Thus, by providing the cutting portion 19, the magnetic gap G can be narrowed, and a large amount of magnetic flux can be induced to the induction coil 16, so that the induced voltage can be increased, and the tweeter piezoelectric The efficiency of the speaker can be improved.

  Further, in the second embodiment, when the induction coil 16 is formed by winding the magnetic metal wire around the cutting portion 19, the outer diameter of the induction coil 16 is not made smaller than the outer diameter of the yoke pole 11. The depth d of the groove of the cutting portion 19 is “the diameter of the induction coil 16 × the number of turns + the clearance α”. Thus, by setting the depth d of the groove of the cutting part 19, it is possible to maintain a state close to a structure without the cutting part 19.

  Next, a third embodiment of the magnetically coupled speaker according to the present invention will be described with reference to a cross-sectional view of the main configuration shown in FIG. The same parts as those in the first embodiment of FIG. 1 and the second embodiment of FIG. 2A are denoted by the same reference numerals, and detailed description of common portions is omitted because it is duplicated.

  The electromagnetically coupled speaker shown in FIG. 2B has cutting portions 20a and 20b having the same height h at positions that are vertically distributed with respect to the top plate 13 on the outer periphery of the yoke pole 11, for example, symmetrical positions. Provided. An induction coil 16 made of iron wire is wound around the cutting portion 20a provided on the upper outer periphery of the yoke pole 11.

  On the other hand, the cutting part 20b provided at the lower end of the outer periphery of the yoke pole 11 is provided in order to balance the imbalance in the flow of magnetic flux due to the provision of the cutting part 20a on the upper side of the yoke pole 11. However, since the iron content is apparently increased by the amount of the iron wire wound as the induction coil 16 in the upper cutting portion 20a, the depth of the groove of the lower cutting portion 20b is the same as that of the upper cutting portion 20a. If the depth of the groove is d, it is formed as 1/2 of that. By configuring in this way, more magnetic flux can be induced to the induction coil 16, the induction voltage can be increased, and the efficiency of the tweeter piezoelectric speaker can be improved.

It is sectional drawing of the principal part structure which shows 1st Example of the electromagnetic coupling type speaker which concerns on this invention. FIG. 5 is a half-sectional view of a main part configuration showing second and third embodiments of an electromagnetically coupled speaker according to the present invention. It is principal part sectional drawing which shows the conventional electromagnetic coupling type speaker.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Yoke 11 Yoke pole 12 Magnet 13 Top plate 14 Coil bobbin 15 Voice coil for woofer 16 Inductive coil 17 Cutting part 18 Lead wire 19 Cutting part 20a, 20b Cutting part G Magnetic gap

Claims (4)

A woofer voice coil disposed in a magnetic gap formed between the center hole of the top plate constituting the magnetic circuit and the yoke pole, a diaphragm added to the woofer voice coil, and a magnetic field generated in the woofer voice coil In a combined electromagnetically coupled speaker comprising an induction coil for magnetic coupling arranged inside and a tweeter speaker driven by the induced voltage of the induction coil,
An electromagnetically coupled speaker, wherein a cutting portion is provided on an outer periphery of a yoke pole near the inside of a woofer voice coil, and an induction coil is wound around the cutting portion. A woofer voice coil disposed in a magnetic gap formed between the center hole of the top plate constituting the magnetic circuit and the yoke pole, a diaphragm added to the woofer voice coil, and a magnetic field generated in the woofer voice coil In a combined electromagnetically coupled speaker comprising an induction coil for magnetic coupling arranged inside and a tweeter speaker driven by the induced voltage of the induction coil,
A cutting part is provided on the outer periphery of the upper end of the yoke pole, and the cutting part is formed so that the lower end of the induction coil is positioned higher than the upper end of the woofer voice coil at the maximum amplitude of the woofer voice coil. An electromagnetic coupling type speaker characterized by winding a coil. A woofer voice coil disposed in a magnetic gap formed between the center hole of the top plate constituting the magnetic circuit and the yoke pole, a diaphragm added to the woofer voice coil, and a magnetic field generated in the woofer voice coil In a combined electromagnetically coupled speaker comprising an induction coil for magnetic coupling arranged inside and a tweeter speaker driven by the induced voltage of the induction coil,
Cutting portions are provided at positions separated from the top plate on the outer periphery of the yoke pole, and an induction coil is wound around the upper cutting portion, and the groove depth of the lower cutting portion is set to the upper cutting portion. An electromagnetic coupling type characterized in that it is formed shallower than the depth of the groove, and the unbalanced magnetic flux generated by providing the upper cutting part is balanced by the lower cutting part. Speaker.   2. The induction coil is formed by winding a magnetic metal wire around the cutting portion, and configured to prevent a decrease in magnetic flux in a magnetic gap of a magnetic circuit due to the provision of the cutting portion. The electromagnetically coupled speaker according to any one of claims 1 to 3.

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