JPS59148500A - Dynamic speaker - Google Patents

Abstract

PURPOSE:To obtain a space with high magnetic flux density by opposing magnetic poles magnetized the same of a couple of cylindrical or columnar magnets and driving a diaphragm by a voice coil interlinked with the magnetic flux vertical to the axial direction of the magnets generating from the opposing part. CONSTITUTION:A couple of the cylindrical magnets 1, 2 are arranged so that the same magnetic poles (e.g., the N poles) are opposed via a disc spacer respectively. In this state, the magnets 1, 2 are fixed to a frame 5 by a fixing screw 4. Since the magnetic poles magnetized the same of the magnets 1, 2 respectively are opposed, the magnetic flux generated from the entire region of the N poles is diverged from the circumference of the spacer 3. Thus, a strong magnetic field is formed around the counter part of the magnets 1, 2.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a dynamic speaker.

BACKGROUND TECHNOLOGY AND PROBLEMS Generally, in dynamic speakers, a ring-shaped air gap is provided in a part of the magnetic path that includes a magnet having an N@S radius, and a voice coil is placed in the high magnetic flux density space formed in this air gap. and is configured to perform electro-mechanical conversion. Therefore, in order to obtain the required magnetic flux density, a magnet of sufficient volume and associated magnetic path materials (yokes and pole pieces) are required.As a result, the device tends to be large and heavy, and the loop The space occupied by the magnetic path material is large, and the voice coil must be placed in a narrow cap, which reduces the degree of freedom in design and makes it difficult to process and assemble the soft iron core material used as the magnetic path material. is necessary.

Purpose of the Invention In view of the above-mentioned problems, the present invention can obtain a space with sufficient magnetic flux density with an extremely simple structure, and if necessary, can eliminate the use of magnetic path materials, thus eliminating the above-mentioned drawbacks. The purpose of this invention is to provide a dynamic type speaker.

Summary of the invention.

The dynamic speaker according to the present invention includes a pair of columnar or cylindrical magnets (11 (21
The same includes a field device in which polarized magnetic poles are closely opposed, a voice coil (7) interlinked with a magnetic flux generated from the opposing portions of the pair of magnets and perpendicular to the axial direction, and a voice coil (7) in which the voice coil is wound. A diaphragm (9) coupled to a cylindrical bobbin (6)
They are equipped with the following. With this configuration, the structure of the speaker can be extremely simplified and the speaker can be made lighter and smaller.

Example Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a vertical sectional view of a dynamic speaker according to a first embodiment of the present invention. In this embodiment, a pair of cylindrical magnets C (II (21) are used as the field device.

Each magnet (IH2+) is magnetized in the axial direction of the cylindrical shape, and arranged so that the same magnetic poles (for example, N pole) face each other with a disc-shaped spacer (3) in between. In this state, the magnet ( +1 (2+ is the frame (5) with the fixing screw (4)
I is fixed.

Since the magnetic poles of the magnet (1) +21 have the same polarity facing each other, all the magnetic flux generated from the entire area of the N pole diverges from the circumferential surface of the spacer (3). Therefore, a strong magnetic field is formed around the facing portion of the magnet (11 (21). The spacer (31) may be made of a magnetic material such as a soft iron core material, or may be made of a non-magnetic material such as a synthetic resin. If the spacer (3) has a soft iron core, it becomes more difficult to increase the vertical component of the magnetic flux optically measured from the opposite part of the magnet (+1[2+).

Also, each P1 pole of the magnet (ll+21) may be brought into close contact without using the spacer (3).The fixing screw (4) must be made of a non-magnetic material (brass, aluminum, etc.), but instead of using the fixing screw The frame (5) may be fixed using an adhesive or a tightening band.Since the frame (5) does not have a function as a magnetic path, it may be a general structural member such as soft iron.

A voice coil (7) wound around a bobbin (6) is placed in the magnetic field I formed around the opposing parts of the magnets (11+21).The upper end of this bobbin (6)
8) and is supported by the frame (5) and connected to the oscillating plate (9) in the shape of a dwarf cone. The upper end of the diaphragm (9) is fixedly supported by the frame (5) via the edge portion (10).

According to the configuration shown in Fig. 1, a magnetic field with a large magnetic flux density can be created without forming a magnetic field wr including narrow nine gaps, so the volume of the magnet can be reduced, and a magnetic path material such as soft iron can be used. Since it is possible to create a strong magnetic field even without it, the overall structure can be made lightweight, small, and cheap. Furthermore, since the voice coil does not need to be placed in a narrow gap, there is a high degree of freedom in the shape and placement of the voice coil.

As shown by the imaginary line in FIG.
The magnetic flux diverging from the opposing portion of the 2+ may be converged on the yoke member (II) to increase the density of the magnetic flux interlinking with the heis coil (7). In this case, frame 1h (!'il
is formed by '+i' due to magnetic path deviation.

FIG. 2 is a longitudinal sectional view of a speaker showing a second embodiment of the invention. In this example, a cylindrical magnet, (1++2
Similarly to FIG. 1, the N poles are arranged so that, for example, their N poles face each other via a link-like substrate 3). Note that the magnet (11 (!: (21) and these frames (5)
The mounting method may be a screw fixing method similar to that shown in FIG. 1, or an adhesive may be used as described above.

A voice coil (7) wound around a bobbin (6) as in FIG. Furthermore, a second voice coil (+4) wound around the bobbin (131) is installed around the inner periphery of the opposite part of the magnet (11 (21), and a second voice coil (+4) wound around the bobbin (131) 2 cone-shaped diaphragms (19 are attached).
51 is fixed to the perturbation surface of the first diaphragm (9) via the edge portion +IE.

The diaphragms (9) and (19) are multi-driven for bass and treble sounds, respectively, through a filter network or individually. According to the embodiment shown in FIG. 2, the same effect as in FIG. 1 can be obtained. In addition, since both the outer and inner magnetic fluxes of the opposing portion of the magnet 11 (21) are used, a coaxial two-way speaker can be obtained without increasing the number of magnetic components.

FIG. 3 is a longitudinal sectional view of a speaker showing a fifth embodiment of the present invention. In this example, a cylindrical magnet (
11 (A field device with 21 magnetic poles facing each other is used,
A voice coil (force (1)
41 are arranged. The tip end of each bobbin f61 (13) is connected to one diaphragm (9). Therefore, the diaphragm (9) is driven by two voice coils +71 (14). Therefore, the driving force can be doubled with only one field device, resulting in an extremely efficient speaker. By adjusting the coupling position of the bobbin (61 (11)) to the diaphragm (9), the structure shown in FIG. , one voice coil (
For example, (sword) is used for driving, and the other voice coil (e.g.
j HA031 ) can be used as a vibration detection coil for MF B (motional feedback).

By appropriately feeding back the signal corresponding to the movement of the diaphragm (9) detected by this vibration detection coil to the amplification device that drives the voice coil (7), it is possible to improve the frequency characteristics and damping factor. can.

Note that when the voice coil (14) is used as a height detection coil for MFB, this coil (1) is magnetically isolated from the drive side by the cylindrical magnet (11+21), so leakage magnetic flux on the drive side Vibration plate (9) without being affected by
It is possible to accurately detect only the vibrations of

Next, FIG. 4 is a longitudinal sectional view of a speaker showing a modification of FIG. 3. In this example, the plane diaphragm (Ryo 6) is driven in parallel.The diaphragm (bobbin + 61F + 3 on the back of IgI) is arranged in a cylindrical shape and added, and the voice coil is wound around each +7HI41 is a magnet (11(2
It is arranged so as to interlink with the magnetic flux generated from both sides of the + facing part. With this configuration, an effect similar to that of the embodiment shown in FIG. 6 can be obtained in a flat speaker. However, in the above-mentioned embodiment, since the magnetic flux is concentrated in a narrow space, when an excessive input occurs to the voice coil, It is possible to provide a nonlinear characteristic such that the vibration 8[11 (stroke) characteristic of the diaphragm in response to an input is saturated and a sound pressure level above a certain level is no longer generated. Therefore, it is suitable for use in applications where excessive input is expected, such as a reproduction speaker for an electric guitar.

Effects of the Invention As described above, the present invention has a pair of cylindrical or cylindrical magnets m (2+ magnetic poles of the same polarity facing each other, and magnetic flux generated from the opposing portions that is orthogonal to the axial direction of the magnets and (iJ intersecting points).・
The f-soil is used to drive the diaphragm. At f, the magnetic rotation is y1 as in the past, and a narrow valley opening is provided inside to create a high magnetic flux density. In order to obtain a time interval, it is possible to obtain a sufficient sieve with only a pair of magnets, and to simplify the sieve 4. It can be made light and compact.Also, there is no need to configure a closed loop magnetic circuit including 4 gaps, so the shape and arrangement of the boy's coil can be difficult.
A ten degrees of freedom can be combined.

[Brief explanation of drawings]

11th floor I is a longitudinal sectional view showing a first flow example of a dynamic type speaker to which the present invention is applied; 6th
FIG. 4 is a vertical cross-sectional view of a flat speaker showing a modification of FIG. 6. FIG. In addition, in the symbol - used in the drawing ζ, (IX2+...... Magnet (3)...
・・・・・・・・・・・・Spacer (4)・・・・・・
・・・・・・Fixing screw (5)・・・・・・・・・
・・・・・・Fre 18(6)・・・・・・・・・・・・
...Bobbin (71)...Voice coil 8)...Damper (9)...・・・・・・・・・Vibration plate (1
0)・・・・・・・・・・・・Edge part. Agent Souvenir Katsu〃 Tsune Kao Yoshio〃 Toshitaka Sugiura

Claims (1)

[Claims] A field device is installed in which the magnetic poles of a pair of columnar or cylindrical magnets magnetized in the axial direction are closely opposed to each other, and magnetic flux and chains perpendicular to the axial direction are generated from the opposing portions of the pair of magnets. A dynamic speaker comprising a voice coil that intersects with the other and a diaphragm connected to a cylindrical bohin around which the voice coil is wound.