JP4019493B2 - Coaxial type speaker device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an improvement of an on-vehicle coaxial type speaker device.
[0002]
[Prior art]
As a coaxial type (coaxial type) loudspeaker device that has been widely used as a composite loudspeaker device, both high and low frequencies coming out from the loudspeaker unit of each band are emitted from substantially the same position, and are summarized briefly. Therefore, it is widely used for in-vehicle use.
[0003]
FIG. 4 is a partial cross-sectional view of the most common coaxial type speaker device. In the speaker device of FIG. 4, reference numeral 20 denotes a coaxial type speaker device as a whole. The speaker device 20 includes a speaker unit 20L for low sounds (or low and medium sounds) and a speaker for medium and high sounds (or high sounds). The unit 20H is configured.
[0004]
The yoke 4 constituting the magnetic circuit of the low-frequency speaker unit 20L is made of a disk-shaped plate material, and a cylindrical center pole 4a planted in the center and a stepped portion are formed concentrically so as to surround the center pole 4a. And a magnet 3 magnetized in the thickness direction in a ring shape in which the inner diameter is fitted to the magnet guide portion 4b of the yoke 4 and joined to the magnet guide 4b. The ring-shaped plate 1 joined to the upper surface of the magnet 3 with an adhesive or the like, and a steel-made funnel-shaped frame 7 fixed on the plate 1 constitute a magnetic circuit of a metal part.
[0005]
In the concentric magnetic gap portion 17 between the center pole 4a and the plate 1, in order to insert the voice coil 8a wound around the voice coil bobbin 8, a spacer such as kraft paper is wound around the inner periphery of the voice coil bobbin 8. In this state, the voice coil bobbin 8 is inserted into the center pole 4 a from above, and the position of the voice coil 8 a is set so as to be disposed in the magnetic gap portion 17.
[0006]
A corrugated concentric damper 9 is joined with an adhesive or the like between the intermediate outer diameter portion of the voice coil bobbin 8 and the outer periphery of the bottom surface of the frame 7, and the inner diameter portion of the cone 10 with the funnel-shaped fixed edge 13 is further joined. The voice coil bobbin 8 is fitted and joined to the outer diameter of the upper end portion thereof, and the maximum diameter portion of the cone 10 is joined to the maximum diameter opening portion of the frame 7 through the gasket 12.
[0007]
Further, the outer diameter portion of the damper 9 is joined to the outer periphery of the bottom surface portion of the frame 7, and after the adhesive is dried, the spacer inserted into the inner diameter of the voice coil bobbin 8 is pulled out. Then, it is fixed to the upper surface of the center pole 4a via an adhesive or a screw.
[0008]
Further, a cap 14 having a through-hole 14 a in the center so as to penetrate the support column 2 is stuck on the inclined portion of the cone 10, and the mid-high sound speaker unit 20 H is fixed on the support column 2.
[0009]
The configuration of the above-described middle / high tone speaker unit 20H is an electrodynamic type having the same configuration as that of the above-described low / medium tone speaker unit 20L.
[0010]
The lead wires are connected to the input terminals 15a and 15b via the tinsel wire 16 from the voice coil 8a of the above-described low-pitched sound speaker unit 20L and middle / high-pitched sound speaker unit 20H, and sound is transmitted to the voice coil 8a via the input terminals 15a and 15b. Supply signal. In the above description, the case of assembling the pre-magnetized magnet 3 has been described. However, the non-magnetized magnet 3 may be magnetized at the final assembly stage.
[0011]
[Problems to be solved by the invention]
Since the above-described coaxial type speaker device is disposed in a relatively small space for in-vehicle use or the like and is driven with a large amount of power, the heat radiation from the voice coil 8a wound around the voice coil bobbin 8 is very large. In the vicinity of the magnetic gap 17 and in the first space 18 a formed between the lower surface of the damper 9 and the upper surface of the plate 1 and in the second space 18 b formed between the center pole 4 a and the inner diameter of the magnet 3. There was a problem that heat was accumulated and it was difficult to release heat. For this reason, the frame 7 and the voice coil bobbin 8 are made of cast aluminum alloy to enhance the heat dissipation effect. However, the heat dissipation effect is not necessarily perfect.
[0012]
The present invention seeks to provide a coaxial type speaker device that solves the above-mentioned problems. The problem to be solved by the present invention is that the struts are formed in a polygonal shape to improve radiation efficiency and the first and second space portions. An attempt is made to obtain a coaxial type speaker device capable of releasing heat accumulated in the vicinity to the outside of the cone 10.
[0013]
[Means for Solving the Problems]
The present invention is a coaxial type speaker device in which a speaker unit for middle and high sounds is coaxially disposed on a column erected from the center pole of the magnetic circuit of the speaker unit for bass, wherein the column is formed of an aluminum alloy, The cross-sectional shape is a polygon in which a plurality of grooves are formed in a columnar shape along the longitudinal direction of the column .
[0014]
According to the coaxial type speaker device of the present invention, the column has a polygonal shape and the surface area is increased to increase the radiation area, and the heat of the space in the magnetic circuit is transferred to the cone 10 through the groove formed in the column. What can be effectively radiated to the outside is obtained.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the coaxial speaker device of the present invention will be described in detail with reference to FIGS. In the present invention, parts corresponding to those of the speaker shown in FIG.
FIG. 1A is a partial cross-sectional view of the coaxial speaker device of this example, and FIG. 1B is a cross-sectional view taken along line AA ′ of FIG.
[0016]
In FIG. 1A, reference numeral 3 denotes a coaxial type speaker device as a whole, including a low-frequency speaker unit (or including a low / mid-range speaker unit) 20L and a medium / high-frequency speaker unit (or a high-frequency speaker unit). ) 20H is combined with a coaxial type (hereinafter referred to as a coaxial type).
[0017]
The low-frequency speaker unit 20L has an electrodynamic type speaker unit configuration, and the yoke 4 includes a disk-shaped portion made of a plate material such as pure iron, and a columnar center pole 4a erected at the center position of the disk-shaped portion. A magnet guide portion 4b composed of a step portion formed concentrically with the center pole 4a and formed in a disk-like portion is integrally formed.
[0018]
A ring-shaped magnet 3 magnetized in the thickness direction of ferrite or the like is bonded onto the disk-shaped portion of the yoke 4 with an adhesive. The inner diameter of the ring-shaped magnet 3 is fitted and positioned in the step portion of the magnet guide portion 4b formed in the disc-shaped portion of the yoke 4.
[0019]
A ring-shaped plate 1 is joined to the magnet 3. In this case, the gap guide is left inserted in the center pole 4a, an adhesive is applied to the upper surface of the magnet 3, and the inner diameter of the plate 1 is inserted into the outer diameter of the gap guide to be bonded and fixed. The plate 1 is made of pure iron or the like in the shape of a disk, and a voice coil 8a is formed in a magnetic gap 17 formed between the inner peripheral edge of the through hole and the outer diameter of the center pole 4a. Arranged.
[0020]
A metal part of a magnetic circuit is constructed by fixing a frame 7 formed in a funnel shape with steel, aluminum alloy or the like to the plate 1. Below the magnetic gap 17, the outer circumference of the center pole 4 a and the inner diameter of the magnet 3 are formed. A second gap 18b surrounded by is formed.
[0021]
A voice coil 8a wound around a voice coil bobbin 8 that can be made of a cylindrical aluminum alloy or the like is inserted into the magnetic gap portion 17 of the above-described magnetic circuit, and has a corrugated corrugation that can vibrate in the vertical direction. The voice coil bobbin 8 is held through a damper 9 having a characteristic.
[0022]
The inner diameter of the damper 9 as described above is bonded to the middle portion of the voice coil bobbin 8 via an adhesive, and the outer diameter portion is bonded to the outer periphery of the bottom surface portion of the frame 7. Further, the inner diameter of the funnel-shaped cone 10 having a free or fixed edge 13 made of paper or the like is joined to the upper outer diameter portion of the voice coil bobbin 8, and the maximum diameter portion of the cone 10 is connected to the peripheral edge of the upper opening of the frame 7. It fixes through the gasket 12.
[0023]
Next, an adhesive is applied to the upper surface of the center pole 4a constituting the magnetic circuit to join the support column 2 that supports the middle / high tone speaker unit 20H. Alternatively, it can be fixed more firmly via screws 5 or the like.
[0024]
A material such as an aluminum alloy for die casting (for example, ADC12) is used for the support 2 as shown in the plan view and the side view of FIGS. In JIS, etc., 13 types such as Al—Si, Al—Mg, and Al—Si—Cu are defined for this aluminum alloy for die casting. Any of these types of materials may be used. . For example, as shown in the plan view of FIG. 2A, the center hole or the through hole 2b is formed at the center position of the columnar shape, and the five semicircular grooves 2a are formed at angular positions that are equally divided from the center of the column. Is formed along the longitudinal direction of the cylinder, the cross-section is polygonal, and the heat radiation efficiency is increased as a shape that increases the surface area of the outer periphery of the cylinder as compared to the cylindrical rod.
[0025]
Since such a shape is cast by injecting a die-casting aluminum alloy into a die in a molten state, a free cross-sectional shape can be accurately produced in large quantities.
[0026]
Therefore, the cross-sectional shape of the column is not limited to the shape shown in FIG. 2A, and can be selected as a polygon, a star, or the like. Of course, it is good also as the support | pillar 2 with a groove | channel in the longitudinal direction obtained by the drawing method using polygonal shapes, such as aluminum alloy for training.
[0027]
After the support 2 as described above is fixed to the upper surface of the center pole 4a, the upper end of the voice coil bobbin 8 or the inclined portion of the cone 10 has a dome-like shape with a through hole 14a at the center, and is attached with a lightweight material such as aluminum. The cap 14 formed together with the mating portion 14b is inserted into the support column and joined to the inclined portion of the cone 10 with an adhesive so as to cover the upper end of the voice coil bobbin 8 in an airtight manner.
[0028]
As described above, the medium / high sound speaker unit 20H constituting the outer-magnet type electrodynamic speaker unit structurally similar to the low sound speaker unit 20L is fixed to the support column 2 fixed on the center pole 4a by an appropriate mounting method. Thus, the coaxial speaker device 20 is obtained.
[0029]
Accordingly, an air passage is formed between the through hole 14a of the cap 14 and the support column 2 in the groove 2a portion communicating vertically with the longitudinal direction of the support column 2 as shown in the AA cross-sectional arrow view of FIG. Will be.
[0030]
The maximum diameter of the column 2 made of a conventional cylindrical rod is about 24 mmφ in a coaxial speaker device with a maximum output of about 200 W. However, the maximum diameter of the polygonal column in this example is made as thin as possible, and the voice coil bobbin 8 The third space 18c is formed between the inner diameter portion and the maximum diameter of the polygonal column.
[0031]
The tinsel wire 16 is connected to the voice coil 8a, and an audio signal is supplied to the voice coil 8a via input terminals 15a and 15b attached to the frame 7.
[0032]
By assembling the speaker device as described above, the first space portion 18a between the cone 10 and the upper surface of the plate 1 and the above-described second and third space portions 18b and 18c are formed.
[0033]
The operation of the coaxial speaker device having the above configuration will be described with reference to FIG. 3 corresponding to those in FIG. 1 are assigned the same reference numerals and redundant description is omitted, but in the configuration of FIG. 3, radiation having a plurality of fins in the support column 2 in order to further enhance the heat dissipation effect of the support column 2. The plate 21 is fixed.
[0034]
In FIG. 3, an acoustic signal is supplied to the input terminals 15a and 15b to drive the low-pitched speaker unit 20L and the mid-high-pitched speaker unit 20H, and in the vicinity of the magnetic gap portion 17 heated by heat generated by the current flowing through the voice coil 8a. The heat of the plate 1 and the center pole 4a is transmitted to the frame 7 and the column 2 and is emitted from the outer surface of the frame 7 and the column 2 having a large surface area and the heat radiation plate 21.
[0035]
Furthermore, the air heated in the vicinity of the first, second, and third spaces 18a, 18b, and 18c is, for example, air in the first space 18a with respect to the amplitude in the F direction of the cone 10. The magnetic gap 17 between the outer diameter of the plate 1 and the voice coil 8a passes through the damper 9 having good characteristics, and the second gap 18b → the magnetic gap 17 between the inner diameter of the voice coil bobbin 8 and the outer diameter of the center pole 4a. → The voice coil bobbin 8 flows into the third space 18 c inside the inner diameter and is radiated in the radial direction of the cone 10 through the air passages of the plurality of grooves 2 a formed between the cap 14 and the support column 2.
[0036]
Accordingly, the heated air in the first to third space portions 18a, 18b, 18c is discharged to the outside of the cone 10, and even a speaker device arranged in a narrow place like a vehicle-mounted coaxial speaker device is sufficient. Can be cooled.
[0037]
Examples of specific cooling effects of the present invention will be shown below.
(A) The coaxial speaker device having a cone diameter of 170 mm and an output voltage of 200 W of the speaker unit for bass and having a maximum diameter of 22 mm of the polygonal column shown in FIG. 2 has a surface area larger than that of the columnar column having the same diameter in FIG. Only by taking a large amount, the cooling temperature could be lowered by 8 ° C., and it could be lowered by 10 ° C. by the air flow discharged by the groove 2 a provided in the column 2.
[0038]
【The invention's effect】
According to the coaxial speaker device of the present invention, the heat radiation area of the support supporting the speaker unit for middle and high sounds erected on the center pole constituting the magnetic circuit of the speaker unit for bass is increased, and the die casting with good radiation efficiency is performed. There is an aluminum alloy that does not rise in temperature beyond the specified value even if it is used for in-vehicle use by radiating the heat in the magnetic circuit or magnetic gap to the outside of the cone through the groove formed in the support column. can get.
[Brief description of the drawings]
FIG. 1 is a side sectional view of a coaxial speaker device of the present invention.
FIGS. 2A and 2B are a plan view and a side view of a support column used in the coaxial speaker device of the present invention. FIGS.
FIG. 3 is an explanatory diagram of an air discharge operation of the coaxial speaker device of the present invention.
FIG. 4 is a side sectional view of a conventional coaxial type speaker device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Plate, 2 ... Prop, 3 ... Magnet, 8 ... Voice coil bobbin, 8a ... Voice coil, 9 ... Damper, 10 ... Cone, 14 ... Cap, 20 ... Speaker device, 20L ... ... Low-frequency speaker unit, 20H ... Medium / high-frequency speaker unit

Claims (4)

A coaxial type loudspeaker device in which a middle / high tone speaker unit is coaxially disposed on a column erected from a center pole of a magnetic circuit of a bass speaker unit,
A coaxial type speaker device , wherein the column is formed of an aluminum alloy, and the cross-sectional shape thereof is a polygonal shape in which a plurality of grooves are formed in a columnar shape along the longitudinal direction of the column . 2. The coaxial speaker device according to claim 1 , wherein a through hole is provided in the center of a cap disposed on the upper surface of the voice coil bobbin of the low frequency speaker unit, and the polygonal column is installed in the through hole . 2. The coaxial speaker according to claim 1, wherein the cross-sectional shape is formed with five semicircular grooves along the longitudinal direction of the cylinder at an angular position that is equally divided into five from the cylinder center of the column. apparatus. The coaxial speaker device according to claim 1 or 3, wherein the groove along the longitudinal direction is formed by a method of drawing an aluminum alloy.

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