JPS6138679B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electroacoustic transducer, and particularly to a novel loudspeaker that exhibits excellent acoustic properties and is inexpensive in manufacturing and material costs, and a method for manufacturing the same.
Although this system can be manufactured relatively easily through mass production using highly advanced automation, the performance of each individual loudspeaker can be maintained unimpaired and manufacturing tolerances can be kept within narrow limits. It is something.

As mentioned above, the object of the present invention is to have low material and manufacturing costs for each part, to be easily applicable to advanced automation technology, and to have fairly small manufacturing tolerances, and to provide a loudspeaker to a baffle plate of a loudspeaker system. The method of attaching the voice coil spider to the loudspeaker basket is inexpensive and reliable, and the method of attaching the voice coil spider to the loudspeaker basket is simple and economical, and maintains a high level of performance. We do not use external means such as washers, adhesives, damping agents, etc. that tend to generate noise, and eliminate the vibration or hum of the basket against the front panel. Furthermore, we have adopted a high gap magnetic flux density, and the air load on the cone is virtually eliminated. To provide a loudspeaker and a method for manufacturing the same, which are standardized in terms of design, have sufficient strength at the flange portion, and control the sealing function of flutter components between the loudspeaker and the baffle. Further, other objects of the present invention are as follows. The area of the flange in contact with the baffle should be approximately on the same plane, giving a uniform compressive force to the gasket, and aligning the shaft center with the installation hole drilled in the baffle to install the driver. The mounting screws should be screwed into the baffle plate perpendicular to the main surface of the flange to prevent damage by applying unexpected force to the opening edges of the baffle plate. Ensure that the spider flange, roll flange of the cone, protrusions or individual parts in each component, etc. are aligned axially as expected with the through hole of the front magnetic pole plate. and to maintain the relative height and position of the flange and the front magnetic pole plate reliably and with good reproducibility.
The fluorocarbon magnetic pole plate must be held in place when it is assembled into the capsule, the front magnetic pole plate must be fixed with sufficient mechanical rigidity, and the front magnetic pole piece must be secured to the periphery of its through-hole. A notch or keyway is provided in a part of the corn roll part to make positioning with respect to the speaker terminal accurate and reproducible, and the corn roll part is not provided with a puddle, and the winding is kept in one direction. Avoid bending in the opposite direction, the size of the speaker relative to the baffle plate must be kept within relatively narrow manufacturing tolerances, and the surface that engages with the baffle plate should be flat, and the connection terminal for connecting the cord should also be installed. , to disclose a convenient method that does not require insulating strips or auxiliary fastening means, etc., and to use a generally planar spider that is convenient and suitable and has sufficient stability during extension and retraction. , ventilation holes, and terminal butt parts are made by two-part molding, etc., to uniformly distribute the air load, reduce stress concentration on sharp parts, and make it possible to use standard diameter rods when molding. In the end, the molding cost can be reduced.

Generally speaking, the loudspeaker of the present invention includes a plastic basket containing a front pole plate made of a low reluctance magnetic material. Preferably, the magnetic pole plate is formed by stamping.
An undercut is provided at the edge portion to be advantageous when molding the magnetic pole plate inside. The shape is preferably octagonal, with an opening coaxially drilled in the center and notches radially outward from the edge of the opening, so that the voice coil, the return lead wire from the rear end of the coil to the front, and the cylindrical magnetic pole body. (pole piece) shall be fit to receive. The cylindrical pole body is preferably press-fitted or press-fitted into a coaxial opening in a rear pole plate made of a magnetic material with low reluctance, and the rear pole plate is also preferably octagonal in shape and is similar to the front pole. An annular permanent magnet is tightly sandwiched together with the plate, so that a high magnetic flux level can be obtained between the air gap between the opening of the front magnetic pole plate and the pole piece.

The plastic basket is preferably provided with an annular flat section in front of the front pole plate to which the voice coil spider (preferably flat in general) is secured. A desirable fixing method is to use a spider having a porous periphery, apply heat to the annular plane part below the periphery to melt the surface part, and allow the melted plastic material to flow into the pores around the spider's periphery. Heat is removed and the plastic is cooled to solidify.

Preferably, the plastic basket is provided with a pair of tabs radially outward from the surface, with openings communicating with the tabs, and the tabs are spaced apart from each other to serve as insulation and mechanically support the terminal. The voice coil lead and connection can be made to this terminal through the above-mentioned opening. Preferably, the surface extending radially forward and outward from the annular surface to which the spider is fixed to another annular surface (parallel to the front magnetic pole plate) that supports the edge of the cone has a substantially A plurality of uniformly arranged ventilation holes are opened to uniformize the air load on the cone. Desirably, each opening is elliptical, and the distance between adjacent openings is shorter than the minor axis diameter of the elliptical opening. The two openings facing the tab receiving the speaker terminal are preferably larger than the other openings and are capable of receiving a circular punch or punch having a pin at the rear end, or rather, a punch or punch that has a pin at the rear end. It is formed into an elliptical shape. The speaker terminal tab has an opening that receives a speaker terminal.

It is preferable that a rim rises vertically from the surface that supports the edge of the cone to protect the roll portion of the edge. The upper end surface of the rim portion is preferably a flat installation surface parallel to the magnetic pole plate. Three mounting tabs spaced angularly apart are preferably provided to increase installation stability. These tabs may have openings for receiving screws or the like, and the openings may serve as guides to keep the screws vertically inserted into the baffle.

Further, a plurality of rim portions may be provided extending between adjacent mounting tabs, so that a so-called twist-end-lock method may be adopted in which the rim portion is fixed by twisting the baffle after being fitted into the baffle.

Preferably, ribs may be provided on the outer circumferential surface of the basket that extend in the radial direction and extend toward the mounting tabs to assist in centering and aligning the basket when placed within the mounting hole of the baffle. It is also possible to arrange a plurality of studs parallel to the front magnetic pole plate and with their top surfaces positioned between the annular plane parts to which the edges of the spider and cone are respectively fixed, so that the loudspeakers can be stacked in series. good.

In the manufacturing method, the front magnetic pole plate is first positioned at the rear of a basket molding mold, and when the plastic material is poured into the mold and the basket is molded, the front magnetic pole plate is embedded integrally with the plastic material. Preferably, the front magnetic pole plate is formed by stamping, and is provided with an undercut portion, which generally occurs when punching metal due to the clearance of a punching die, so that the front pole plate has an undercut portion that slopes radially inward toward the rear of the die. Preferably, the plastic material flows behind the front end of the pole plate to increase the force with which the pole plate is held in place after cooling. The periphery of the voice coil spider (preferably flat in overall view) is positioned on the first annular flat surface, and heat is applied to the surface through the periphery to destroy the plastic in that area. The plastic may be melted and flowed into the peripheral porous portion of the spider in the direction of the heat source;
The heat source is then removed and the plastic re-hardens, establishing a firm connection between the spider periphery and the surface. Due to the precision of assembly after molding and, therefore, the accuracy of the positioning of the notches in the pole plates, the preferably single-layer helical voice coil pre-assembled on the mandrel will notch the portion of the winding that passes over the turn at its fold. It can be inserted accurately through the spider by passing it through the inside. The presence of the notches allows a single-layer helical voice coil with folded and overlapping lead portions as described above to be used without magnetic flux loss. Magnetic flux loss occurs because it has to be made larger all at once. When assembled on the assembly mandrel,
After the coil is inserted, an adhesive, such as alpha cyanoacrylate, is applied to the annular plane supporting the edge of the cone. This adhesive is effective in securing corn roll sections of urethane and other porous materials. The essentially flat nature of the surface may contribute to the adhesive's uniform curing characteristics within 2 seconds. After the joints have hardened, the mandrel can be removed and the entire device can be completed using techniques that would normally be used by those skilled in the art. If a cloth corn roll is used, the same fixing technique as described above for spider fixing may be used.

Other objects and features of the present invention will become clearer in the following description based on the illustrated embodiments.

FIG. 1 first shows an exploded perspective view of an embodiment of the electroacoustic transducer or loudspeaker of the present invention, and the plastic basket 11 has an octagonal front ( front)
A magnetic pole plate 12 is embedded. The basket is also provided with a plastic tab 13 for mounting a speaker terminal 14 which connects to the voice coil lead 18 as best seen in FIG. The rear octagonal magnetic pole plate 16, which also has low magnetic resistance, has an opening in the center, into which a pole piece 17 is press-fitted and fixed. The pole piece 17 is positioned within and surrounded by a central opening 22 of an annular permanent magnet 21 having high magnetic energy. The outer periphery of the plastic basket 11 is provided with ribs 23, in this case three, extending radially outward, as clearly shown in FIGS. 2, 5 and 6.
This also serves as a sealing means for positioning the central axis of the loudspeaker when the loudspeaker is inserted into the speaker installation opening formed in the baffle plate. Furthermore, a plurality of substantially elliptical ventilation holes 24 are continuously opened in a series along the circumference in the intermediate portion between the spider 25 and the annular outer edge installation lip 26 of the cone 27 on the outer circumference of the basket 11. . Voice coil bobbin 31
carries the voice coil 32 (Fig. 2), and as shown in Fig. 3, the cone 27 and spider 25
and is fixed. As shown in the second figure, a dust cover (dust cover) 33 covers the opening at the tip of the bobbin 31.

The voice coil 32 is preferably a single-layer winding of aluminum wire with a special surface treatment (no insulation coating process; anodized) with a rectangular cross section.
1 is also preferably made of anodized aluminum and has a slit 31A in the axial direction.
The rear winding end 15A of the coil extends forward across the winding portion of the coil and parallel to the keyway 54'. This creates an air gap.
It is possible to minimize the distance between air gaps, eliminate the waste of magnetic flux in the air gap, maximize the magnetic flux utilization rate, and thus the loudspeaker efficiency, as well as provide a thin layer of oxide film as an insulating material suitable for conductive materials. Because of this, many windings can be tightly wound within the gap, and the inertia can be made relatively low, leading to high efficiency. Furthermore, in practice,
Even when nine loudspeakers are connected in series, such as the commercialized Bose 901 loudspeaker disclosed in U.S. Pat. No. 3,582,553, single-layer winding reduces the Since it is easy to keep the impedance, for example, to about 0.9Ω, it is possible to obtain a nominal impedance of 8Ω in series (speakers with this impedance value are generally used). Further, the bobbin 31 can also be easily formed by wrapping an aluminum sheet around a mandrel.

FIG. 2 is a diametrical cross-sectional view of the first illustrated embodiment with terminal 14 installed.
Note that the same reference numerals indicate the same components throughout the figures.
As mentioned above, the air gap in which the voice coil 32 is housed is the air gap between the pole piece 17 and the front magnetic pole plate 12, but the inner surface of the bobbin 31 should not touch the pole piece 17. Furthermore, the voice coil 32 is positioned in such a way that it does not touch the radially inner circumferential surface of the front magnetic pole plate.

The plastic basket 11 has an annular flat section 3 above and parallel to the front pole plate 12.
4 is formed, and the peripheral edge 35 of the spider 25 is fixed here. Preferably, the fixing method is to apply heat just below the melting temperature to the annular plane part 34 through the peripheral edge 35 and cause the material to flow into the pores or the foamed material that is the material of the peripheral edge 35. is good. If the heat is then removed, the plastic material will solidify in that state, and the spider 25 will be held truly parallel to the front magnetic pole plate 12 and exactly perpendicular to the central axis of the driver, and its peripheral edge 35 will be fixed to the annular flat part 34. can do.

The plastic basket 11 has this annular plane part 34 and another annular plane part 36 parallel to the pole plate 12, where the periphery (commonly called edge) 26 of the cone 27 is exposed to the adhesive or heat as described above. In addition, it is fixed by any suitable method, such as by melting the plastic material under the edge and then removing heat.

A lip 37 rises perpendicularly from the annular surface portion 36, and its upper end surface 42 is parallel to the surface portion 36, the annular plane portion 34, and the front magnetic pole plate 12, and serves as an annular surface that engages with the bubble plate. As it becomes,
The height of the lip is sufficient to protect the rolled portion 41 of the edge of the cone 27.
As will be described below with reference to FIG. 9, this lip 37 can also provide a sealing function. Immediately below the annular surface portion 36 are the surface portion 36, the annular plane portion 34, and the upper end surface 4.
2. An annular surface portion 43 is placed parallel to the front magnetic pole plate 12 and also serves as an engaging portion for the baffle plate. This surface portion 43 also contributes to accurate positioning of the driver and provides a sealing action in conjunction with a commonly used gasket. Although only one is shown in FIG. 2, there are three through holes 44, preferably equiangularly spaced, through which fixing screws can be passed. It is best to make this through hole so that its axis is perpendicular to the plane of the baffle, and that it has approximately the same diameter as the fixing screw so that there is no gap as much as possible, so that the fixing screw can be accurately attached to the baffle. Since it is screwed in vertically, there is no chance of it breaking or being bent diagonally and sticking out of the hole.

The basket 11 is also provided with three ribs 23 that extend radially outward toward the plane portion including the installation hole 44, and are arranged to align the driver with the central axis when the driver is housed in the baffle. centering).

FIG. 3 shows a connecting portion between the bobbin 31, the cone 27, and the spider 25. That is, this is achieved by using an adhesive medium 45 such as a thermosetting adhesive such as an epoxy resin.

As clearly shown in the plan view of FIG. 4, 26 elliptical openings 24 (circular in projection) are bored in the basket, and the speaker terminals are slotted in the basket. Two large elliptical openings 51 are bored in the portions facing the tabs 13 held within 52. The minor axis diameter of the elliptical opening is the same as the diameter of the circular opening, which appears circular when projected onto a plane as shown in FIG. The angle between the radii passing through the center lines of the openings 51 of the basket 11 is 25° as shown, so that each center line of the openings 51
The angle is set at 12 1/2 degrees, and the opening 2
The adjacent angular spacing of the center lines of 4 is 12°. opening 2
The short axis diameter of No. 4 is about 6.4 mm (1/4 inch), and the distance between adjacent opening edges is preferably shorter than that. In any case, good and uniform ventilation is obtained in this way. Regarding the arrangement of the openings, the part that deviates from the uniform and symmetrical relationship as described above is that the opening facing the speaker terminal tab 13 is larger, but this allows tab molding in the normal molding process. This is for the purpose of

By setting the number and spacing of the openings as ventilation holes as described above, the flow of the material in the radial direction during molding is not restricted, and the number of ribs, narrowness of the ribs, etc. , it is possible to ensure a uniform flow of material and to obtain uniform strength regardless of the rotational position after installation. Such a symmetrical arrangement produces rigidity, concentric radial shrinkage after molding, and radial shrinkage does not affect the speaker function.

The plastic basket 11 also has five angularly equally spaced stepped portions 53 whose upper planes are connected to the rear pole plate 46, the annular plane portion 34,
36 and within a plane located between the annular plane parts 34 and 36. This stepped portion 53 is useful for stacking the baskets when transporting or stacking them before assembling them into a speaker. A radial notch 54' cut into the front pole plate 12 is angularly positioned approximately 30 DEG from the bisector radius of both tabs 13 and serves as an accurate reference guide during loudspeaker assembly.

The part of the plastic basket 11 that serves as the installation opening 44 has tabs 5 arranged at equiangular positions.
4 (three as shown), upright rims 37 extend circumferentially between adjacent tabs, each rim being provided with a protrusion 55, and complementary rim portions of the baffle as described below. The loudspeaker is adapted to engage a groove provided therein to permit so-called snap-in insertion of the loudspeaker. Opening 44 may not be particularly necessary for such fixation techniques. Conversely, the assembled loudspeaker may be fixed in the radial direction, such as by screwing screws or other suitable fixing means into a conventional baffle through the openings 44 (in the case shown, three-point support is used). In this case, the annular plane part 43 is usually placed in the same plane as the baffle surface, that is, on the surface.

Figure 4 Figure 5 shows a cross section taken along line 5-5.
During the above description, the vertical positional relationships of some constructs will become clearer.

FIG. 6 is also a reference drawing, and is a side view seen from the line 6--6 in FIG.

Figure 7 shows the above-mentioned regular octagonal front magnetic pole plate 12.
The material is preferably a magnetic material with low magnetic resistance, such as hot-rolled pickled oil-treated magnetic steel equivalent to model numbers C-1010 to C-1018, and there are notches 54 in the figure. ′ is shown.

FIG. 8 is a cross-sectional view of the front magnetic pole plate 12 taken along the line 8-8 in FIG. That will be understood. If such an undercut is provided, the flow of the plastic will be improved during molding, and the octagonal front magnetic pole plate will be firmly fixed embedded in the plastic basket 11.

The back plate 16 is similar to the front magnetic pole plate, but differs in that the diameter of its central opening is slightly smaller in order to press fit the pole piece 17 therein, and that it is not provided with a keyway or notch. The octagonal shape of both magnetic pole plates 12, 16 saves material in manufacturing compared to the use of round magnetic pole plates, which are the circumcircles of the octagons. Considering that the magnetic pole plates are made equal in terms of area, the distance between opposing sides of an octagonal magnetic pole plate will be smaller than the diameter of a circular magnetic pole plate with the same effective area, but even so,
From the standpoint of the magnetic circuit, it has been found that an octagonal magnetic pole plate is sufficient.

FIG. 9 shows a portion of a baffle suitable for mounting the loudspeaker of the embodiment described above, and the baffle is also preferably made of plastic. An opening 62 is opened in the baffle plate 61, and the peripheral edge thereof is an annular surface 63 that is lowered one step.
3 is in close contact with this surface 63. The diameter of the opening 62 is
Preferably, it is just large enough to accommodate the portion of the basket 11 below the surface 43. There are three equally angularly spaced groove structures 64 that are open at the counterclockwise facing edge and adapted to receive the tabs 54 and have notches 65.
is provided to engage with the protrusion 55 of the basket 11. The height of the slit in the groove structure 64 is preferably slightly less than the thickness of the tab 54 so that when the loudspeaker is rotated clockwise to engage the protrusion 55 in the notch 65, the tab 54
When firmly assembled, the outer peripheral surface of the lip portion 37' forms a wall surface 66 that is perpendicular to the baffle 61.
closely engage with. As a result, the loudspeaker can be hermetically fixed without using a soft material such as a gasket or moltite, and without using screws, thereby reducing costs and improving reliability. If desired, screws or other fasteners may be screwed through the openings 44.

As one specific example, the loudspeaker of the present invention, as embodied in the Bose 901 loudspeaker system manufactured by the applicant, has a diameter of approximately 11.4 cm (4.1/2 cm).
inch), and the dimensions, materials, etc. of each part are listed for reference.

The material of the plastic basket is thermoplastic polyester such as GE's Valox.
Contains ~30% glass fiber.

Outer diameter of the annular plane part 36: Approximately 11.18 mm (4.4 inches) Inner diameter: Approximately 10.06 cm (3.96 inches) Height of the rim 37 above the annular plane part 36:
Approximately 0.64 cm (0.25 inch) Thickness of the annular plane part 36: Approximately 0.19 cm (0.075 inch) Distance between the plane parts 36 and 34: Approximately 1.80 cm (0.712 inch) Outer diameter of the annular plane part 34: Approximately 7.79 cm (3.07 inch) Inner diameter: approx. 7.01 cm (2.76 inches) Distance between the same surface portion 34 and the magnetic pole plate 12:
Approximately 0.69 cm (0.27 inches) Outer diameter directly below surface portion 36: Approximately 10.28 cm (4.05 inches) Outer diameter at the plane including magnetic pole plate 12: Approximately 8.61 cm (3.39 cm)
(inch) Thickness of magnetic pole plate 12: Approximately 0.45 cm (0.18 inch) Same distance between sides: 7.62 cm (3 inches) Same Center opening diameter: Approximately 2.76 cm (1.088 inch) The preferred assembly order for the above embodiment is as follows. street.

1 back plate 16, ball piece 17,
A permanent magnet 1 is assembled using an anaerobic adhesive.

2 Insert the terminal 14 into the tab 13.

3 Spider positioning and installation.

4. Insert the voice coil assembly with voice coil 32.

5 Apply adhesive to the root side and the roll edge installation side of the cone.

6. Fix the corn roll edge 26 to the surface part 36.

7 Installing the wire, fixing the dust cap, soldering work, and attaching the magnetic function.

Although a new and effective loudspeaker has been disclosed as detailed above, there is no need to be limited to the embodiments described above.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view of an embodiment of the loudspeaker of the present invention, FIG. 2 is a vertical sectional view of the same embodiment, FIG. 3 is an enlarged sectional view of a part of the main part of FIG. 2, and FIG. 4 5 is a sectional view taken along the line 5-5 in FIG. 4, FIG. 6 is a side view of the basket taken along the line 6-6 in FIG. 4, and FIG. The figure is a plan view of the front magnetic pole plate in the same embodiment, Figure 8 is a sectional view taken along line 8-8 in Figure 7, and Figure 9 is a part of a baffle suitable for assembling the loudspeaker of the same embodiment. This is a plan view. In the figure, 11 is a plastic basket, 12 is a front magnetic pole plate, 16 is a rear or back magnetic pole plate,
17 is a pole piece, 21 is a permanent magnet, 24 is a ventilation hole, 25 is a spider, 32 is a voice coil, 3
4 and 36 are annular flat parts, 37 is a rim, 54 is a tab, and 61 is a baffle.

Claims (1)

[Scope of Claims] 1. A loudspeaker comprising: front and rear magnetic pole plates made of a magnetic material with low magnetic resistance; and a plastic basket enclosing the front magnetic pole plate but not enclosing the rear magnetic pole plate. 2. The loudspeaker according to claim 1, wherein the front magnetic pole plate is formed by punching and has a fractured surface as an undercut, and the undercut functions when molded into a basket. is located at the rear of a plastic basket, and the annular portion around the pole plate is the rear of the plastic basket. 3. The loudspeaker according to claim 1, wherein the front magnetic pole plate has an octagonal shape and has a central opening in which a central cylindrical pole piece and a voice coil can be received. speaker. 4. The loudspeaker according to claim 3, wherein the rear magnetic pole plate has a central opening, and a cylindrical pole piece made of a low magnetic resistance magnetic material is disposed within the central opening of the rear magnetic pole plate. Fit tightly,
An air gap for receiving the voice coil is defined between the opening of the front magnetic pole plate, and a permanent magnet is sandwiched between the front and rear magnetic pole plates and surrounds the central pole piece, and together with these, a magnetic field is created within the air gap. A loudspeaker consisting of 5. The loudspeaker according to claim 1, wherein the plastic basket is provided with a first annular plane section disposed parallel to and in front of the front magnetic pole plate, and the voice coil spider is arranged in front of the front magnetic pole plate. A loudspeaker including means for supporting the periphery of the pole plate while being parallel to the pole plate. 6. A loudspeaker according to claim 5, comprising means for fixing the peripheral edge of the voice coil spider to the first annular plane. 7. A loudspeaker according to claim 6, wherein the means for fixing the peripheral edge of the voice coil spider to the first annular plane portion is a plastic material constituting a plastic basket. 8. The loudspeaker according to claim 5, wherein a pair of tabs protrudes radially outward from the first annular plane, each tab having a separate conductor terminal. A loudspeaker which is inserted in a spaced apart and insulating manner, and a lead wire from a voice coil is connected to the terminal through an opening near the tab. 9. The loudspeaker according to claim 8, wherein each tab has a single conductor terminal inserted therein. 10 The loudspeaker according to claim 5, which extends forward and radially from the first annular plane part that receives the spider to the second annular plane part that is parallel to the front magnetic pole plate and receives the edge of the cone. It has a surface extending outward in the direction, and a plurality of uniformly arranged ventilation holes are perforated in the surface that connects the two mutually parallel annular plane parts, thereby preventing a uniform air load from being applied to the cone. loudspeaker that can give you 11. The loudspeaker according to claim 10, wherein each of the plurality of ventilation holes has an elliptical shape, and the distance between adjacent hole edges is shorter than the minor axis diameter of the hole. 12. The loudspeaker according to claim 7, wherein the plastic bust has a pair of tabs radially outwardly from the first annular plane, each tab having a terminal for insertion of a conductor. The basket also has a surface portion extending forward and radially outward from a first annular flat surface portion that receives the spider to a second annular flat surface portion that is parallel to the pole plate and receives the edge of the cone. A plurality of uniformly arranged elliptical ventilation holes are provided in the plane part that connects the two plane parts in parallel, and uniform air load is applied to the cone of the loudspeaker.
The distance between adjacent hole edges of the hole is shorter than the diameter of the shortened hole axis, while the opening facing the terminal-receiving tab is larger than other ventilation holes, and the opening facing the terminal-receiving tab is larger than the other ventilation holes and receives the punching tool with the pin at the rear. A loudspeaker which is formed into an elliptical shape by a punching tool and has a speaker terminal tab and an opening formed therein so as to be able to receive a speaker terminal. 13. The loudspeaker according to claim 12, wherein the plastic basket is provided with a rim extending perpendicularly to the second annular plane supporting the edge of the cone at the most distal end of the plastic basket. The loudspeaker is designed to protect the roll part of the loudspeaker. 14. The loudspeaker according to claim 13, wherein the plastic basket includes:
A mounting tab is provided extending radially outwardly from a second annular flat surface supporting the edge of the cone, the tab having a through hole perpendicular to the flat surface for threading the screw into the mounting baffle. The loudspeaker is designed to be placed vertically. 15. A loudspeaker according to claim 14, wherein the raised rim is divided into a plurality of sections each extending between adjacent mounting tabs, and is secured to the baffle by a twist-end-lock method. A loudspeaker that has become possible. 16. The loudspeaker according to claim 15, wherein the radially outwardly extending surface of the bust is provided with a rib extending radially toward the installation tab, and the rib is disposed within the baffle installation opening. Loudspeakers designed to help center time. 17. The loudspeaker according to claim 1, in which a plurality of annular planes whose upper planes are parallel to the front magnetic pole plate are provided between the annular plane part supporting the spider and the annular plane part supporting the edge of the cone. A loudspeaker provided with studs to permit alignment between loudspeaker assemblies. 18. The loudspeaker according to claim 4, wherein the rear magnetic pole plate is octagonal. 19. The loudspeaker according to claim 10, wherein the front and radially extending surface portion has a plurality of angularly arranged stepped portions, the front surface of which is connected to the first annular plane portion. It lies in a parallel plane and its diameter is approximately equal to the diameter of the rear end of the basket.
A loudspeaker that can be stacked by placing the back of another basket on top of it. 20. A loudspeaker according to claim 1, in which the front magnetic pole plate has a central opening for receiving the ball piece and the voice coil, and the means including the pole piece communicates a magnetic field with the opening. 1. A loudspeaker defining an air gap exhibiting an air gap and having means for supporting a voice coil within the gap. 21. A loudspeaker according to claim 10, comprising a loudspeaker cone,
A loudspeaker in which the periphery of the cone is fixed to a second annular plane. 22. A loudspeaker according to claim 21, wherein the means for fixing the periphery of the cone to the second annular plane is a plastic material of the basket. 23. The loudspeaker according to claim 10, comprising a tab disposed at an angle from the second annular plane portion and serving as an engagement portion for the baffle. 24. The loudspeaker according to claim 23, wherein each tab has a small diameter hole,
The axis of the hole is perpendicular to the second annular plane, such that the fixing means to the baffle are guided perpendicularly to the plane. 25. The loudspeaker according to claim 23, wherein three tabs are provided around the second annular plane part at equal angular intervals. 26. The loudspeaker according to claim 4, wherein the pole piece has a tapered rear end and is press-fitted and fixed into the central opening of the rear magnetic pole plate. 27. The loudspeaker according to claim 11, wherein the elliptical ventilation hole has a circular shape when projected onto a plane parallel to the second annular plane. 28. The loudspeaker of claim 1, wherein at least one of the magnetic pole plates has opposing parallel surfaces, one of which is coplanar with the circular magnet, and one having eight side surfaces substantially perpendicular to the parallel plane between the parallel planes;
each of its sides has an inner end in contact with the circular magnet, an outer end substantially parallel to the inner end, and two ends common with adjacent side faces, and at least one inner end of the pole plate a loudspeaker in which a portion of the loudspeaker is housed within an area bounded by an outer diameter of the circular magnet. 29. The loudspeaker of claim 28, wherein the inner edge of the at least one pole plate defines an area of approximately 83 percent of the surface area defined by the outer diameter of the circular magnet. speaker. 30. The loudspeaker of claim 28, wherein both said pole plates have eight sides and their inner ends are contained in the area bounded by the outer diameter of said circular magnet. 31. The loudspeaker according to claim 30, wherein the eight side surfaces form a regular octagon. 32. The loudspeaker according to claim 28, wherein the eight side surfaces form a regular octagon. 33. The loudspeaker according to claim 29, wherein the eight side surfaces form a regular octagon. 34. A loudspeaker including a basket, a diaphragm, and means for defining an air gap having a magnetic field, comprising: front and rear pole plates made of a low magnetic resistance magnetic material; a plastic basket that does not enclose the voice coil, and a voice coil that is wound in a single layer, the rear end of the conductor constituting the coil being folded over the layers from one end of the single layer to the other end, The front pole plate is provided with a notch extending radially from a central opening of the front pole plate and having a cross-sectional area slightly larger than the folded portion of the voice coil conductor. 35. The loudspeaker according to claim 34, wherein the single-layer winding is wound by turn from anodized aluminum having a rectangular cross section, such that there is no mechanical separation between each adjacent winding. Although they are in close contact, they are electrically insulated, the winding diameter is slightly smaller than the air gap diameter, and the voice coil resistance is at least 1.
A loudspeaker that is smaller than an ohm and that can provide a moderate nominal impedance when multiple loudspeakers are connected in series to form a single loudspeaker system. 36. The loudspeaker according to claim 35, which is applied to a system using nine loudspeakers with voice coils connected in series,
A loudspeaker whose nominal impedance is approximately 8 ohms. 37. A loudspeaker as claimed in claim 34, comprising an anodized aluminum bobbin disposed within an air gap, the single layer winding being made by winding the bottle; Each winding is made of anodized aluminum with a rectangular cross section, and each adjacent winding is mechanically close but electrically insulated, and the winding diameter is slightly smaller than the air gap diameter. loudspeaker. 38. The loudspeaker according to claim 37, wherein the bobbin has a slit extending along its entire length in the axial direction.