JPH04639Y2 - - Google Patents

Description

[Detailed description of the invention] "Purpose of the invention" (Field of industrial application) The present invention relates to a dome-shaped speaker, in particular, the dome part, the coil bobbin part, and the edge part extending horizontally from the lower end are integrated. This invention relates to a dome-shaped speaker that incorporates a dome-shaped diaphragm that is molded and has a roughly "straw hat" shape in cross section.

(Prior Art) A conventional dome-shaped speaker is constructed as shown in the sectional view of FIG. 4A and the partially enlarged view of FIG. 4B. In the figure, reference numeral 20 denotes an external magnetic circuit section, which consists of a yoke 21, a center pole 22, a magnet 23, a top plate 24, etc., and each member is fixed with adhesive.
When forming the gap, a jig having a cylindrical portion corresponding to the gap is fitted onto the center pole 22, and the top plate 24 is fixed with adhesive. Reference numeral 30 denotes a vibration system, which may be one in which the dome-shaped diaphragm portion 31 and the coil bobbin portion 32 are integrally formed and a curved edge portion 33 is separately bonded thereto, or the dome-shaped diaphragm portion 31 and the edge portion 33 are integrally formed. The mounting member 2 is molded and the coil bobbin part 32 is adhered thereto.When assembling, the outer periphery of the edge part 33 is attached to the mounting step part 26 formed on the top plate 24.
7 and 27, thereby placing the voice coil 34 at a predetermined position within the gap 25 and covering it with the frame 40. It is assembled as a vibration system assembly so that it is in the correct position.

(Problems to be solved by the invention) In the conventional dome-shaped speaker shown in FIGS. 4A and B described above, various jigs are used in each assembly process. Because it is necessary to set the clearance,
These clearances, dimensional tolerances of each part, variations in work, etc. become cumulative errors, causing the gap spacing to become large or uneven, resulting in a decline in performance. Furthermore, in conventional dome-shaped speakers, since adhesives are used to fix each member, time is required for the adhesives to dry and solidify, resulting in time loss in the assembly process.

Additionally, in conventional dome-shaped speakers, a large dip generally occurs before the high-frequency resonance frequency, resulting in a significant drop in effective sound pressure radiation, and the cause of this is generally axially asymmetric resonance. etc. are known.

The purpose of this invention is to eliminate the above-mentioned conventional drawbacks,
Each component can be assembled easily and accurately without using adhesives or jigs, and the gap can be made as narrow as possible to increase the magnetic flux density, and the gap interval can be made uniform for a uniform magnetic flux distribution. The object of the present invention is to provide a dome-shaped speaker which can be made into a flattened dip in terms of frequency characteristics.

"Structure of the invention" (Means for solving the problems) The dome-shaped speaker according to the invention is formed by integrally molding a dome part, a coil bobbin part, and an edge part extending horizontally from the lower end of the dome part. A dome-shaped diaphragm is formed, and a guide portion for arranging an edge is formed in a portion of the inner peripheral edge of the top plate located on the magnet side, and the outer peripheral edge of the edge portion is fitted into the guide portion, and a flexible edge pressing member is provided. and assembled by tightly fitting a part of the guide part formed on the top plate into the engaging part provided on the upper outer peripheral edge of the center pole,
The base of the dome portion of the dome-shaped diaphragm is pressed by a braking member made of a flexible material or the like disposed on the upper surface of the top plate to provide braking.

(Function) A magnetic member is arranged on the yoke, and with the edge part of the dome-shaped diaphragm being held between the edge holding members, it is fitted and set into the guide part formed on the top plate, and the engagement provided on the upper outer periphery of the center pole is set. A part of the guide portion formed on the top plate is positioned and press-fitted into the top plate. As a result, the magnetic member is clamped and fixed between the yoke and the top plate, and a portion of the guide portion of the top plate is tightly fitted into the engaging portion of the center pole, so that the top plate is accurately fixed, while the diaphragm is The outer peripheral end of the edge portion is centered and set while being guided by the inner wall of the guide portion, and the voice coil is accurately set within the gap, and the edge portion is held between the edge pressing members. When the magnet member is magnetized in this assembled state, the yoke and top plate are attracted and fixed more firmly.

A frame is attached to the upper surface of the top plate, and a braking member made of a flexible material such as urethane foam is disposed so as to be supported by the inner peripheral edge of the frame, thereby holding down the base of the dome portion of the diaphragm. to apply braking.

When assembling as described above, adhesive is not required and there is no time loss for drying and solidifying, and the assembly process can also be simplified. Moreover, by assembling as described above, a predetermined gap is automatically formed between the outer peripheral surface of the upper end of the center pole and the inner peripheral surface of the top plate.
No jigs or the like are used to form this gap, and the outer peripheral edge of the dome-shaped diaphragm is guided by the back wall of the guide portion of the top plate and is automatically centered, allowing the voice coil to form the gap. Since it is automatically set at a predetermined position within the center pole and there is no need for a jig to set the diaphragm, etc., there is no need to set an unnecessary gap interval, and the gap between the outer circumferential surface of the upper end of the center pole and the inner circumferential surface of the top plate is The dimensions can be set so that the minimum gap required for movement of the coil bobbin and voice coil is formed. This makes it possible to increase the magnetic flux density and improve efficiency, and the gap formed as described above becomes uniform over the entire circumference, making the magnetic flux distribution uniform and reducing distortion etc. be able to.

Since the dome-shaped diaphragm is damped by pressing the dome base with a damping member, the dip that occurs before the high resonance frequency is flattened, as is clear from the frequency characteristic measurement results explained later. can be converted into

(Example) The first example of the dome-shaped speaker according to the present invention is
The description will be given based on FIGS. 3 to 3. FIG. 1 is a sectional view of the dome-shaped speaker, FIG. 2 is a partially enlarged sectional view of the same, and FIG. 3 is a frequency characteristic comparison diagram.

In the figure, 1 is an outer magnet type magnetic circuit section,
It is composed of a yoke 2, a center pole 3, a magnet 4, and a top plate 5. 10 indicates a vibration system, and a dome-shaped diaphragm is a dome part 1.
1. Coil bobbin part 12, edge part 1 formed to extend horizontally from the lower end of the coil bobbin 12
3, it is formed into a roughly "straw hat" shape. 14 is a voice coil.

In the present invention, basically, the dome portion 11
The coil bobbin part 12 and the edge part 13 extending horizontally on the lower end thereof are integrally molded, and the part of the inner peripheral edge of the top plate 5 located on the magnet 4 side, that is, the inner peripheral edge of the lower end, is provided with an edge part 13 for arranging the edge. In the embodiment, the guide part 6 is formed with a stepped part 6a, and the outer circumferential edge 15 of the edge part 13 is fitted into the guide part 6, and is held between edge pressing members 16, 16 made of flexible materials, etc. A part of the guide part 6 formed on the plate 5, a step part 6 in the embodiment
By tightly fitting the inner peripheral edge of the lower end of a into the engaging part 7 provided on the upper outer peripheral edge of the center pole 3,
The assembly of the magnetic circuit section 1 and the arrangement of the vibration system 10 at a predetermined position can be performed at the same time. As a result, the magnetic gap 8 is formed without using a jig or the like, and the voice coil 14 is automatically placed in the correct position within the magnetic gap 8.

Various means are possible for providing the engaging portion 7, but in the embodiment, a stepped portion 3a is formed on the outer periphery of the upper part of the center pole 3, and a cutout portion 3b is formed at the lower portion of the stepped portion 3a. is in the shape of a flange, and its outer peripheral edge is the engaging portion 7.
The lower edge of the stepped portion 6a of the top plate 5 is tightly fitted into the outer peripheral edge of the stepped portion 3a, and the fitting depth is set to be approximately 0.5 mm. In addition, when forming the step part 3a,
For example, a pipe, a ring, or the like made of a non-magnetic material may be fitted into the center pole.

A frame 1 is mounted on the top side of the top plate 5.
A step 5a for arranging a braking member is formed on the inner periphery of the upper surface of the top plate 5, and a ring-shaped braking member 9 made of a flexible material such as urethane foam is arranged on this step. The frame 17 is clamped at the distal end thereof, and the distal end of the braking member 9 presses the base portion 11a of the dome portion 11 to apply braking. In addition, in the figure, 2a is a stepped portion for arranging a magnet. Next, an assembly example will be described. The edge portion 13 is fitted into the stepped portion 6a of the top plate 5 via one edge pressing member 16, and the edge portion 13 is held between the other edge pressing member 16. When the edge portion 13 is fitted into the stepped portion 6a, its outer peripheral edge is guided by the back wall of the stepped portion, so that the diaphragm is automatically centered.
Next, after placing the magnetic member 4 on the yoke 2, the inner peripheral edge of the lower end of the stepped portion 6a is placed on the center pole 3.
position and press fit into the engaging part 7 provided in the. As a result, the magnetic member 4 is clamped and fixed between the yoke 2 and the top plate 5, and the inner peripheral edge of the lower end of the top plate 5 is tightly fitted into the engaging portion of the center pole 3, so that the top plate is properly fixed. Thus, a predetermined magnetic gap 8 is formed without using any jig or the like, and the voice coil 14 is automatically placed at a predetermined position within the magnetic gap 8. When the magnetic member 4 is magnetized in the assembled state as described above, the yoke 2 and the top plate 5 are attracted and fixed more firmly.

A ring-shaped brake member 9 is formed on the stepped portion 5a for arranging the brake member formed on the upper surface side of the top plate 5.
and attach the frame 17. As a result, the tip of the braking member 9 presses the base 11a of the dome portion 11, providing appropriate braking.

FIG. 3 is a frequency characteristic comparison diagram, and as is clear from this comparison diagram, a large dip B occurs in the vicinity of 20,000 to 30,000 Hz without the above-mentioned braking member 9; When placed and applying braking to the base of the dome part, the above dip B
is flattened as shown in A.

By arranging the braking member 9 as described above, in addition to the effect of flattening the frequency characteristics, as a secondary effect, it is possible to prevent dust, iron powder, etc. from entering the magnetic gap 8. It is possible to prevent abnormal noises and disconnections caused by these being rubbed by the voice coil, and it is possible to improve durability. In the above-described embodiment, the braking member 9 is formed into a ring shape and is configured to press the base of the dome portion of the diaphragm over the entire circumference to apply braking. It may also be configured so that it is partially arranged and presses the base of the dome portion in frequency-divided manner to apply braking.

"Effect of the invention" According to the dome-shaped speaker according to the invention, the magnetic circuit unit can be easily and precisely assembled by fitting each member without using adhesives or jigs. In addition, the dome-shaped diaphragm can be assembled at the same time as the magnetic circuit unit, and each member can be automatically placed in a predetermined position, and the magnetic gap can be narrowed and made uniform. As a result, the magnetic flux density can be increased, efficiency can be improved, and distortion and the like can be reduced.

In addition, a damping member made of a flexible material such as foamed urethane placed on the upper surface of the top plate applies damping to the base of the dome portion of the diaphragm, thereby accurately and easily eliminating dips that occur near high-frequency resonance frequencies. Since it can be flattened, it is ideal for this type of dome-shaped speaker for medium and high ranges.

[Brief explanation of drawings]

Figures 1 to 3 show examples of the dome-shaped speaker according to the present invention, in which Figure 1 is a sectional view of the dome-shaped speaker, Figure 2 is a partially enlarged sectional view of the same, and Figure 3 is a comparison diagram of frequency characteristics. It is. 4A and 4B show a conventional dome-shaped speaker, where A is a sectional view and B is a partially enlarged sectional view. DESCRIPTION OF SYMBOLS 1...Magnetic circuit part, 2...Yoke, 3...Center pole, 4...Magnet, 5...Top plate, 5a...Step part for braking member arrangement, 6...
Guide part, 6a... Step part serving as guide part, 7... Engagement part, 8... Magnetic gap, 9... Braking member, 1
0... Vibration system, 11... Dome part, 11a... Dome part base, 12... Coil bobbin part, 13...
Edge portion, 14...Voice coil, 16...Edge holding member.

Claims (1)

[Scope of utility model registration request] The dome-shaped diaphragm has a dome part, a coil bobbin part, and an edge part formed extending horizontally from the lower end of the dome part, and a guide part for arranging the edge in the part located on the magnet side of the inner periphery of the top plate. is formed, and the outer peripheral edge of the edge part is fitted into the guide part, and is held by a flexible edge pressing member, and a part of the guide part formed in the top plate is attached to the upper outer peripheral edge of the center pole. The base of the dome portion of the dome-shaped diaphragm is pressed by a braking member made of a flexible material or the like disposed on the upper surface of the top plate to provide braking. A dome-shaped speaker featuring