JPH067396U - Speaker - Google Patents

Abstract

(57) [Abstract] [Purpose] A single magnet is used to form two magnetic gaps in the magnetic path, and the two magnetic gaps are symmetrically wound above and below a single bobbin. To obtain a small, lightweight, and thin magnetic circuit in a speaker in which each voice coil is arranged. [Structure] A single bobbin 7 connected to a diaphragm 15 is provided in magnetic gaps 5 and 6 which are vertically symmetrically formed by an upper plate 1 and a lower plate 2 which are fixed above and below a magnet 3, and a center pole 4. In a speaker in which voice coils 8 and 9 which are symmetrically wound on the upper and lower parts of the bobbin 7, a window 10 is formed between the voice coils 8 and 9 of a bobbin 7, and an upper plate 1 and a lower plate are formed. A non-magnetic joint 11 for holding the center pole 4 concentrically with respect to 2 penetrates the window 10 and is arranged so as to straddle the inner circumference of the magnet 3 and the outer circumference of the center pole 4.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 In the present invention, one magnet is used, and magnetic gaps are formed at two places in the magnetic path, and the two magnetic gaps are symmetrically divided and wound around a single bobbin. The present invention relates to improvement of a magnetic circuit unit in a speaker in which voice coils are arranged.

[0002]

[Prior art]

 Conventionally, the impedance rise of the voice coil in the high range is suppressed to prevent the efficiency of the treble from decreasing, and the nonlinearity of the drive system is canceled to suppress the distortion of the reproduced sound, or in stereo. As shown in FIG. 5 and described in Japanese Utility Model Laid-Open No. 63-23896, one magnet 23 is used for the purpose of obtaining the left and right sum signal reproduced sounds in the ultra low frequency range by a simple means. Then, the upper plate 21 and the lower plate 22 fixed to the upper surface and the lower surface of the magnet 23 form magnetic air gaps in the upper and lower portions of the center pole 24, respectively, and a single bobbin 27 is formed in the two magnetic air gaps. A speaker in which voice coils 28 and 29, which are symmetrically wound on the upper and lower parts, are arranged, has been put into practical use. In FIG. 5, 31 is a vibrating plate, 32 is a frame for holding the vibrating plate, 33 is an edge of the vibrating plate, and 35 is a damper.

[0003]

[Problems to be solved by the device]

 In the conventional speaker having such a structure, in order to hold the upper plate 21 and the lower plate 22 and the center pole 24 concentrically, both the lower plate 22 and the center pole 24 are provided at the bottom of the magnetic circuit. Since the yoke 30 fixed across the ridge is used, there is a problem to be solved that the magnetic circuit part becomes heavy and large.

In view of the above, the present invention solves the drawbacks of the conventional example described above, and directly supports the center pole by the joint from the magnet sandwiched between the upper and lower plates to reduce the thickness after assembly. , To provide a speaker with multiple voice coils.

[0005]

[Means for Solving the Problems]

 A speaker according to the present invention for achieving the above object will be described with reference to FIGS. 1 to 3 showing an embodiment. In the first invention, an upper portion fixed to an upper surface and a lower surface of a ring-shaped magnet 3 is provided. The magnetic gaps 5 and 6 are formed symmetrically above and below the center pole 4 by the plate 1 and the lower plate 2, and a diaphragm 15 is coupled to the upper and lower magnetic gaps 5 and 6 at one end. 1. A speaker comprising voice coils 8 and 9 wound symmetrically around the upper and lower parts of a bobbin 7, wherein slits or windows 10 are provided at a plurality of positions between the voice coils 8 and 9 of the bobbin 7. In addition to the formation of the slits, a plurality of joints 11 made of a non-magnetic material for holding the center pole 4 concentrically with respect to the magnet 3, the upper plate 1 and the lower plate 2 are provided with the slits 10. It is a speaker, characterized in that through to being arranged straddling the inner peripheral surface and outer peripheral surface of the center pole 4 of the magnet 3.

In the second invention shown in the cross section in FIG. 4, a ring-shaped yoke 14 is arranged outside the upper pole 12 and the lower pole 13 fixed to the upper and lower surfaces of the magnet 3, and the yoke 14 is Magnetic gaps 5 and 6 are formed symmetrically above and below the yoke 14 by the inner peripheral surface and the outer surfaces of the upper pole 12 and the lower pole 13, and the upper and lower magnetic gaps 5 and 6 vibrate at one end. In a speaker in which voice coils 8 and 9 are symmetrically wound on the upper and lower portions of a single bobbin 7 to which a plate 15 is fixed, the voice coil 8 and 9 of the bobbin 7 are Slits or windows 10 are formed at a plurality of positions in between, and a plurality of joys made of a non-magnetic material for holding the yoke 14 concentrically with the magnet 3, the upper pole 12 and the lower pole 13 are provided. The The speaker 11 is characterized in that a slot 11 penetrates the slit 10 and is arranged so as to straddle the outer peripheral surface of the magnet 3 and the inner peripheral surface of the yoke 14.

Further, in the above-mentioned first and second inventions, the joint 11 is made of a conductor and has a vertically symmetrical shape.

[0008]

[Action]

 In the speaker having such a structure, the joint 11 for holding the upper plate 1 and the lower plate 2 and the center pole 4 concentrically exists inside the magnetic circuit, and a thin dustproof cloth is provided on the back surface of the magnetic circuit. However, since the supporting member such as the yoke 30 of the conventional magnetic circuit does not protrude, it is possible to obtain a very thin and compact magnetic circuit speaker while having two sets of driving parts.

[0009]

【Example】

 1 to 2, the first embodiment of the present invention will be described in detail. FIG. 1 is a two-dimensional sectional view of a speaker of the embodiment, FIG. 2 is an exploded perspective view of a main part, and each of the two-directional sectional views shown in FIG. 2 is a cross section taken along the main axis O in the vertical direction in the directions of arrows OY and OX shown in FIG.

In the magnetic circuit, an upper plate 1 and a lower plate 2 are fixed to the upper surface and the lower surface of a ring-shaped magnet 3, and a plurality of center poles 4 are made of a non-magnetic material (four locations in this embodiment). Is held from the inner peripheral surface of the magnet 3 so as to be concentric with the upper plate 1 and the lower plate 2 by the joint 11 and the magnetic gaps 5 and 6 are formed symmetrically above and below the center pole 4. There is.

Voice coils 8 and 9 symmetrically wound on the upper and lower portions of a single bobbin 7 are arranged in the two magnetic gaps 5 and 6, and details thereof are shown in FIG. As described above, slits or windows 10 are formed at a plurality of positions in the bobbin 7 between the voice coils 8 and 9, and the joint 11 penetrates through the windows 10 and the inner peripheral surface of the magnet 3 and the center pole 4. Since it is placed between the outer surfaces, the movement of the voice coil is not hindered when the speaker operates.

The magnetic circuit is attached to the bottom of a frame 16, and a diaphragm 15 coupled to the bobbin 7 is held inside the frame 16 so that it can be vibrated by an edge 17 and a damper 18 like a conventional speaker. ing.

A dustproof cloth 19 is attached to the back surface of the magnetic circuit to prevent dust from entering the magnetic gap. In the case of the short voice coil in which the winding width of the voice coils 8 and 9 is shorter than the thickness of the upper and lower plates as in this embodiment, the dustproof cloth 19 is directly adhered to the lower plate as described above. When using a long voice coil, the dust-proof cloth 19 should be separated from the back surface of the magnetic circuit by using the sum of the voice coil protrusion amount and the size corresponding to the maximum amplitude of the speaker, such as a spacer. Of course, you have to do it.

FIG. 3 shows a modified example of the speaker of the present application, in which the joint 11 is made of a conductive non-magnetic material, and the cross section thereof has a symmetrical shape in the vertical direction. The ring 20 is made of a non-magnetic material, and the joint 11 is radially coupled to the ring 20 to be integrated, and the joint is used as a short ring for suppressing current distortion. In such a modified example, not only the magnetic gap but also the joint 11 is made symmetrical in the vertical direction in the vertical direction, because it is the eddy current generated in the joint 11 and the eddy current in each of the upper and lower drive parts. This is because it is necessary to make the effects and effects on the voice coil equally symmetrical.

As another form of the above modification, a structure in which a shallow ring groove is formed in a side surface portion of the center pole 4 excluding a magnetic gap corresponding portion and a conductive non-magnetic ring is fitted into the groove. (Not shown).

Although the magnetic circuit of the above-described embodiment is the outer magnet type, the configuration of the present invention can be adopted even if it is the inner magnet type magnetic circuit. FIG. 4 shows an embodiment of the second invention of the present application, in which the upper pole 12 and the lower pole 13 are fixed to the upper surface and the lower surface of the magnet 3, and the cross section is U-shaped outside the upper pole 12 and the lower pole 13. Further, a ring-shaped yoke 14 is arranged, and magnetic gaps 5 and 6 are formed symmetrically above and below the yoke 14 by the inner peripheral surface of the yoke 14 and the outer side surfaces of the upper pole 12 and the lower pole 13.

Thereafter, as in the first invention, a voice coil 8 symmetrically wound around the upper and lower parts of a single bobbin 7 having a diaphragm 15 fixed at one end in the upper and lower magnetic air gaps 5, 6. 9 are arranged, but slits or windows 10 are formed at a plurality of positions between the voice coils 8 and 9 of the bobbin 7, and the magnet 3 and the upper pole 12 and the lower pole 13 are arranged. A plurality of joints 11 made of a non-magnetic material for holding the yoke 14 concentrically are arranged so as to penetrate the slit 10 and to extend over the outer peripheral surface of the magnet 3 and the inner peripheral surface of the yoke 14. There is. The holding structure of the diaphragm 15 inside the frame 16 is also the same as that of the first invention.

The magnetic circuit of each of the above-described embodiments is divided into an inner peripheral part and an outer peripheral part with a cylindrical surface including a magnetic gap as a boundary and preliminarily processed, and after fitting a voice coil bobbin, If the joint 11 is attached to the center pole, the yoke, or the magnet with a small screw or an adhesive, it can be easily assembled.

Although the speaker according to the present invention has been described above in detail based on the considered typical embodiment, the embodiment of the speaker according to the present invention is not limited to the structure of the above-mentioned embodiment, and The present invention can be appropriately modified and implemented as long as it has the constituent requirements described in the scope of claims for utility model registration, has the effect of the present invention, and has the effects described below.

[0020]

【effect】

 The speaker according to the present invention has the following effects.

(1) As a speaker having a drive section at two locations of a single voice coil bobbin, it prevents an increase in the impedance of the voice coil in the high range to prevent a decrease in the efficiency of the high-pitched section, and prevents the drive system from becoming unusable. It is possible to cancel the linearity and suppress the distortion of the reproduced sound. Therefore, it is possible to obtain a reproduced sound having excellent frequency characteristics and a low distortion rate.

(2) In stereo, the left and right sum signal reproduction sounds in the ultra-low frequency range can be obtained by a simple means.

(3) Since the joint for supporting the center pole or the yoke and the magnet in the concentric state is mounted inside the magnetic circuit, the magnetic circuit section becomes compact.

(4) By using the assembly hinge (joint) also as a short ring, high quality sound can be expected without requiring special parts for improving sound quality.

(5) The same magnetic circuit can be used for both high-quality sound speakers and LR-integrated speakers.

(6) In the case of a speaker in which two coils are provided on the same bobbin, the change in the magnetic flux density depending on the position of the coil can be canceled due to the vertical symmetry of the magnetic circuit and the vertical symmetry of the joint. Therefore, the non-linear distortion is reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view in two directions of a first embodiment of the invention.

FIG. 2 is an exploded perspective view of an essential part for explaining a relationship between a center pole, a voice coil bobbin, and a joint part, and showing a cutting direction in FIGS. 1, 3, and 4.

FIG. 3 is a bidirectional sectional view of a modified example of the first device embodiment.

FIG. 4 is a cross-sectional view in the two directions of the second embodiment of the invention.

FIG. 5 is a cross-sectional view of a conventional magnetic circuit unit.

[Explanation of symbols]

 1 Upper Plate 2 Lower Plate 3 Magnet 4 Center Pole 5 Magnetic Gap 6 Magnetic Gap 7 Bobbin 8 Voice Coil 9 Voice Coil 10 Slit or Window 11 Joint 12 Upper Pole 13 Lower Pole 14 Yoke 15 Vibration Plate 16 Frame 17 Edge 18 Damper 19 Dustproof Cloth 20 ring

Claims (3)

[Scope of utility model registration request] 1. A magnetic air gap (5) symmetrically above and below a center pole (4) by an upper plate (1) and a lower plate (2) fixed to the upper and lower surfaces of a ring-shaped magnet (3), (6) is formed and symmetrically wound around the upper and lower parts of a single bobbin (7) having a diaphragm (15) fixed at one end to the upper and lower magnetic air gaps (5) and (6). In a loudspeaker in which the voice coils (8) and (9) are arranged, slits or windows (10) are formed at a plurality of positions between the voice coils (8) and (9) of the bobbin (7). ) Is formed and a plurality of joints (11) made of a non-magnetic material for holding the center pole (4) concentrically with respect to the magnet (3) and the upper plate (1) and the lower plate (2). ) Penetrates the slit or window (10) A speaker characterized by being disposed so as to straddle the inner peripheral surface of the magnet (3) and the outer peripheral surface of the center pole (4). 2. A ring-shaped yoke (14) is arranged outside the upper pole (12) and the lower pole (13) fixed to the upper surface and the lower surface of the magnet (3), and inside the yoke (14). Magnetic gaps (5) and (6) are formed symmetrically above and below the yoke (14) by the peripheral surface and the outer surfaces of the upper pole (12) and the lower pole (13), and
The upper and lower magnetic air gaps (5) and (6) have vibration plates (1
5) In a speaker in which voice coils (8) and (9) wound symmetrically are arranged on the upper and lower parts of a single bobbin (7) to which the bobbin (7) is fixed. A plurality of slits or windows (10) are formed between the voice coils (8) and (9), and a magnet (3), an upper pole (12) and a lower pole (1) are formed.
3) A plurality of joints (11) made of a non-magnetic material for holding the yoke (14) concentric to the magnet (3) penetrates the slits or windows (10).
A speaker which is arranged so as to straddle the outer peripheral surface of the yoke and the inner peripheral surface of the yoke (14). 3. The speaker according to claim 1, wherein the joint (11) is made of a non-magnetic conductor and has a vertically symmetrical shape.