WO1998047312A1

WO1998047312A1 - Loudspeaker and method of manufacturing the same

Info

Publication number: WO1998047312A1
Application number: PCT/CN1998/000061
Authority: WO
Inventors: Fan Zhang
Original assignee: Fan Zhang
Priority date: 1997-04-14
Filing date: 1998-04-14
Publication date: 1998-10-22
Also published as: CN1207010A; AU6917198A

Abstract

Three different types of loudspeakers are constituted by combining of a plate in form of circular, polygon or rectangle and a plate in form of inter concave corresponding to said plate; a said inter concave plate and a plate corresponding to said inter concave plate; and two said inter concave plates and a thin slice of rare-earth permanent magnetism arranged in periphery of pole piece. A disclosed method for manufacturing the said loudspeakers which inserts the thin slice of pre-polarized rare-earth permanent magnetism into the plate gap between upper magnetic yoke and lower magnetic yoke hollow frame adhered to the space in form of inter concave. The magnetic field density of loudspeaker's magnetic gap can be adjusted manually.

Description

Speaker and preparation method

Technical field

The present invention relates to a speaker, in particular to an electric speaker using a rare earth permanent magnet, and belongs to the field of electrical mechatronic sensors.

Background technique

In the prior art, although the input power of the circulating NdFeB Hi-Fi speakers has been greatly improved, the sensitivity of the speakers is still low, the voice coil is severely heated, and the magnetic circuit structure continues to apply low magnetic energy products in disguise. Design principle of ferrite permanent magnet speaker. Therefore, the technical advantages of high magnetic energy product of NdFeB rare earth permanent magnet materials have not been fully explored. For example, the speakers provided by CN93234253.1 and CN93237215.5 still have the above-mentioned basic defects, so the sensitivity of the product is only 86 ~ 84dB / W / m, and the coverage of the product is also quite narrow. Summary of the Invention

The first object of the present invention is to overcome the shortcomings of the existing technology, provide several novel and reasonable magnetic circuit structures, and the high magnetic energy product of rare-earth permanent magnets can be exploited to the maximum extent. Therefore, it is suitable for Hi-Fi and professional speakers. The field has comprehensively promoted the implementation of high-sensitivity, high-fidelity, high-performance price ratio external magnetic rare earth permanent magnet speakers.

The second object of the present invention is to overcome the technical problem that high internal coercive force permanent magnets in rare earth permanent magnet speakers, especially high-power speakers, are not easily saturated in the overall magnetic circuit, and provide a permanent magnet and magnetic circuit that are similar to conventional speakers. A completely new method of bonding and fixing, a rare earth permanent magnet is pre-saturated on a magnetizer, and then a new method for preparing a speaker through a combination method.

A third object of the present invention is to provide a method for manufacturing a speaker magnetic driver sheath. The sheath can protect the rare earth permanent magnet from impact damage and limit the leakage magnetic field gradient to a smaller range. A new method is used to bond the yoke and the permanent magnet into a whole combined magnetic circuit.

A fourth object of the present invention is to provide a method for adjusting the magnetic field strength of a ring magnetic gap of a speaker, which effectively controls the dispersion of the main electro-acoustic indicators during the mass production of the speaker, and further reduces the distortion of the speaker.

A loudspeaker mainly includes a permanent magnet, a voice coil, a fixed core support, a diaphragm, a basin frame, and a set of magnetic circuits with an annular magnetic gap. The upper yoke of the magnetic circuit is a flat plate made of magnetic material. The central part is provided with a shaft hole, which is usually a circular hole, or a square or regular hexagon hole matching the lower yoke cylindrical pole core; the lower yoke of the magnetic circuit is a piece of the upper yoke An indented flat plate made of magnetic material with a similar projection area. A convex pole shoe is provided at the peripheral portion of the flat plate. A central pole of the concave flat plate is provided with a columnar pole core and has a round or square or regular hexagon. Or a hollow cross-sectional shape, the upper end of which extends into the central shaft hole of the upper yoke and is higher than the outer plane of the upper yoke by a height AH necessary to form a fully symmetrical magnetic circuit, the value of which is several millimeters to tens of millimeters ; At the peripheral portion between the upper yoke and the pole shoe of the lower yoke, a ring-shaped or more than one fan-shaped or strip-shaped rare earth permanent magnet sheet of uniform thickness is provided, They are all in thickness Magnetization polarization; the voice coil is matched with the shaft hole and the columnar pole core, and its optimal cross-sectional shape is a regular hexagon, and the inner corner of each hexagon is replaced by Article 26) A short arc-shaped line segment is provided at the top, the line segment is tangent to both sides of the inner angle, and the center of the circle falls on the angle bisector of the inner angle; the peripheral pole shoes of the lower yoke can also be provided Two or more concave concave convection air holes are evenly distributed, and the bottom of the air holes is flat to the bottom surface of the inner contour of the concave flat plate of the yoke. The upper yoke is a circular flat plate, and the lower yoke is a circular indented flat plate. The upper yoke is a regular polygonal flat plate, and the lower yoke is a regular polygonal concave flat plate. The upper yoke is a rectangular flat plate, and the lower yoke is a rectangular inner concave flat plate.

A kind of loudspeaker, which mainly includes a permanent magnet, a voice coil, a fixed core support, a diaphragm, a basin frame, and a set of magnetic circuits with an annular magnetic gap. The upper yoke of the magnetic circuit is a concave type made of a magnetic material. A raised plate is provided at the peripheral part of the plate, and a shaft hole is provided at the central part of the concave plate. It is usually a round hole or a square or regular six matching the lower yoke cylindrical pole core. A rectangular hole; the lower yoke of the magnetic circuit is a flat plate made of magnetic material equivalent to the projected area of the upper yoke, and a central pole portion is provided with a cylindrical pole core and has a circular or square or regular hexagonal shape A solid or hollow cross-sectional shape whose upper end projects into the central shaft hole of the upper yoke and is higher than the outer plane of the upper yoke by a height necessary to form a fully symmetrical magnetic circuit Δ Η, whose value is several millimeters to several Ten millimeters; at the peripheral part between the upper yoke and the pole shoe of the lower yoke, a ring-shaped or more than one fan-shaped or strip-shaped rare earth permanent Magnet flakes, they are It is magnetically polarized in the thickness direction; the voice coil matches the shaft hole and the columnar pole core, and its optimal cross-sectional shape is a regular hexagon, and a short truncated circle is provided at the top of the inner corner of each hexagon An arc-shaped line segment that is tangent to both sides of the inner angle, and the center of the circle falls on the angle bisector of the inner angle; two or more uniformly distributed inner surfaces may be provided on the peripheral pole shoes of the upper yoke. A concave convection air hole, when the bottom of the air hole is deepest, is flush with the inner bottom surface of the concave flat plate of the yoke. The upper yoke is a circular indented flat plate, and the lower yoke is a circular flat plate. The upper yoke is a regular polygonal flat plate, and the lower yoke is a regular polygonal plate. The upper yoke is a rectangular indented flat plate, and the lower yoke is a rectangular flat plate.

A loudspeaker mainly includes a permanent magnet, a voice coil, a fixed core support, a diaphragm, a basin frame, and a set of magnetic circuits with a ring-shaped magnetic gap. The upper yoke of the magnetic circuit is a recessed flat plate made of magnetic material. A raised pole shoe is provided at the peripheral part of the flat plate, and a central hole of the concave flat plate is provided with a shaft hole. It is usually a round hole or a square or regular hexagon matching the lower yoke cylindrical pole core. A hole; the lower yoke of the magnetic circuit is an inner concave flat plate made of magnetic material equivalent to the projected area of the upper yoke, a convex pole shoe is arranged at the peripheral part of the flat plate, and a central part of the concave flat plate A cylindrical pole core is provided with a solid or hollow cross-sectional shape having a circular or square or regular hexagon shape, the upper end of which extends into the central shaft hole of the upper yoke and is higher than the outer plane of the upper yoke A height ΔΗ necessary to form a fully symmetrical magnetic circuit, the value of which is several millimeters to tens of millimeters; a ring is provided at a peripheral portion between the upper yoke and the pole piece of the lower yoke Or more than one piece Thick fan-shaped or strip-shaped rare earth permanent magnet sheets, all of which are magnetized and polarized in the thickness direction; the voice coil matches the shaft hole and the columnar pole core, and its optimal cross-sectional shape is a regular hexagon A short arc-shaped line segment is provided on the top of each hexagon internal angle, the line segment is tangent to both sides of the internal angle, and the center of the circle falls on the angle bisector of the internal angle; on the upper yoke The peripheral pole shoes of the lower yoke can also be provided with two or more concave concave convection air holes uniformly distributed, and when the bottom of the air hole is deepest, it is flush with the inner bottom surface of the concave flat plate of the yoke. The upper yoke and the lower yoke are each a circular indented flat plate. Each of the upper yoke and the lower yoke is a regular concave flat plate. Replacement page mentioned (Article 26) The yoke and the lower yoke are each a rectangular indented flat plate.

A hollow frame made of a non-magnetically permeable material with sufficient rigidity is inserted into the recessed space of the upper yoke or the lower yoke, and the outer contour surface of the embedded part is well matched with the inner contour surface of the yoke And it is pre-bonded firmly, the outer horizontal plane of the hollow frame is equal to or slightly lower than the millimeter gap of the pole surface of the pole shoe around the yoke, and the outer vertical surface of the hollow frame forms the permanent magnet sheet. In addition, at the appropriate height of the outer vertical surface, more than two vents evenly distributed along the peripheral direction can be provided; a thin-walled sleeve made of non-magnetic conductive material with sufficient rigidity Having smooth inner and outer wall surfaces, the cross-sectional shape of which is matched with the shaft hole of the upper yoke and the columnar pole core of the lower yoke, and one end of the thin-walled sleeve is sleeved on the On the cylindrical pole core, the other end has a tapered smaller cross-sectional shape, so that the upper yoke can be easily fitted into the thin-walled sleeve; the inner wall surface of the thin-walled sleeve and the Description of the yoke pole The vertical outer profile of the slide fits, the outer wall of the thin-walled sleeve and the inner profile of the shaft hole of the upper yoke slide fit, and the optimal value of the slip fit gap does not exceed ten microns ; Using two pairs of clamps to respectively fix the upper yoke and the lower yoke on two parallel horizontal planes and operating one of them to slide the upper yoke along the thin-walled sleeve from the outside to the inside , Using an auxiliary positioning device or plug gauge block to terminate the gliding stroke of the upper yoke and ensure that the gap between the pole surface of the upper yoke and the lower yoke is higher than the thickness of the permanent magnet sheet by a slight installation The optimal value of the gap is not more than several tens of micrometers. A pre-saturated piece of more than one equal-thickness rare earth permanent magnet sheet is inserted into the gap between the pole surfaces of the yoke from the outside and slides to the hollow frame. The fasteners made of non-magnetically conductive material are inserted into three or more uniformly distributed fastening holes on the mounting surface of the upper yoke and the lower yoke. Remove the upper magnet after the magnet is installed in place A clamp and an auxiliary positioning device or a plug gauge block are used to tighten the fastener to apply static pressure to the anastomotic pole surfaces of the yoke and the permanent magnet, and to be pre-coated on the positioning surface or horizontal surface of the hollow frame for bonding. After the agent is cured, the thin-walled sleeve and the lower yoke clamp are removed; the outer joint portion of the upper pole yoke and the lower pole yoke of the anastomosis pole surface of the speaker may also be Applying an adhesive increases its connection strength.

A method for manufacturing a speaker magnetic driver jacket, in which two or more sections of a sheath made of a non-magnetic material are provided along the vertical outer surface of the upper yoke, the lower yoke, and the permanent magnet to tightly wrap the jacket ; The inner profile of the sheath and the vertical outer profile of the upper yoke, the lower yoke, and the permanent magnet are mutually matched, and a cement is pre-coated before assembly; the two or more segments of the sheath The bonding surface between them is also pre-coated with adhesive; static pressure is applied from the outside to the inside of the shroud in the assembly by a clamp or the fastener is provided by a fastener provided between the adjacent sections of the shroud. The sleeve is tightly pressed against the vertical outer profile of the upper yoke, the lower yoke, and the permanent magnet, and the bonding surface between adjacent sections of the sheath is also squeezed. Remove the clamp after curing.

A method for adjusting the magnetic field intensity of a ring magnetic gap of a speaker, along the axis of the cylindrical pole core on the concave flat plate of the lower yoke or on the lower yoke position of the concave air hole of the peripheral pole shoe The center line is evenly provided with two or more adjusting screw holes; a corresponding adjusting screw made of a magnetically permeable material is screwed from the outside to the inside of the adjusting screw hole, and the front end of the adjusting screw has a regular machining outer surface The adjustment screws are all disposed outside the voice coil, and the outer ends of the adjustment screws can also sink into the adjustment screw holes; adjust the depth of entry of the adjustment screws or replace the adjustment screws of different lengths , The magnetic flux leakage between the end of the adjusting screw and the upper yoke or the permanent magnet can be changed, so as to achieve the purpose of adjusting the magnetic field intensity of the ring magnetic gap of the speaker.

(Replacement Article 26) Overview of the drawings

Drawing description:

Fig. 1. A longitudinal sectional view of a speaker embodiment 1.

Figure 2. Longitudinal sectional view of the magnetic circuit of the speaker in the second embodiment.

Fig. 3. Longitudinal sectional view of the magnetic circuit of the third embodiment of the speaker.

Fig. 4. Longitudinal sectional view of the magnetic circuit of the speaker in the fourth embodiment.

Fig. 5. Flat sectional view of a magnetic circuit embodiment 5 with a square yoke.

Fig. 6. Flat sectional view of a magnetic circuit embodiment 6 having a square yoke.

Fig. 7. Flat sectional view of a magnetic circuit embodiment 7 with a rectangular yoke.

Figure 8. Flat sectional view of Example 8 magnetic circuit with a circular yoke.

Figure 9. Planar sectional view of Example 9 of a magnetic circuit with a circular yoke.

Figure 10. Schematic installation of hollow frame structure.

Fig. 11. Schematic diagram of loudspeaker magnetic gap plane and longitudinal section view of columnar pole core embodiment.

FIG. 12. A plan view of an embodiment of a speaker manufacturing method.

FIG. 13 is a schematic longitudinal sectional view of an embodiment of a speaker manufacturing method.

FIG. 14. A longitudinal sectional view of a method for manufacturing a speaker and a method for manufacturing a magnetic driver sheath. Figure 15. Schematic diagram of Embodiment 1 of a magnetic drive jacket.

Figure 16. Schematic diagram of Embodiment 2 of a magnetic drive jacket.

Figure 17. Vertical sectional view of a speaker reciprocating convection ventilation embodiment (node).

Figure 18. Longitudinal section view (node) of an embodiment of a method for adjusting the magnetic field strength of a ring gap.

Figure 19. Plan view of an embodiment of a method for adjusting the magnetic field strength of a ring gap.

The correspondence between the elements and labels of the present invention is as follows:

Upper yoke 101, 201, 301 ... 901; lower yoke--111, 211, 311 ... 911; inner yoke profile--124, 224, 324 ... 924; permanent magnet —— 102, 202, 302 ... 902; Upper yoke platform surface 113, 213, 313 ... 913; Columnar pole cores 103, 203, 303 ...

903; The outer profile of the columnar pole core is 130, 230, 330 ... 430; The columnar pole core cooling holes are 131, 231, 331 ... ···· 931; The basin frame is 105, 205, 305 ·· ···· 905; diaphragms 166, 266,

366 ..... 966; voice coils-120, 220, 320 ... 920; voice coil skeletons-119, 219, 319 ... 919; fixed core pieces 1 1 18, 218, 318 ... 918; pole shoes 129, 229, 329 ... 929; pole faces 100, 200, 300 ... 900; central shaft holes 126, 226,

326 …… 926; Structural space—163, 263, 363 …… 963; Toroidal magnetic gap—110, 210, 310… 910; Concave convection air holes of yoke—117, 217, 317 ... 917; Magnetic force Driver jackets 137, 237, 337 ... 937; inner profile of the jackets 138, 238, 338 ... 938; jacket vents-140, 240, 340 ... 940; hollow Frames-104, 204, 304 ... ... 904; the outer contours of the hollow frame-134, 234, 334 ... 934; the outer vertical surfaces of the hollow frame-122, 222, 322 ... 922; hollow frame Outer horizontal plane-100 ', 200', 300 '... 900'; Hollow frame air vents-164, 264, 364 ... 964; Upper yoke penetration holes-106, 206, replacement pages (the ^26th article) 306 ... 906; lower yoke screw holes 107, 207, 307 ... 907; adjustable leakage magnetic flux 1001; leakage magnetic flux adjustment screw 1002; adjustment screw 1003; yoke fastener One-to-one 0109; Thin-walled bushing-0108; Fixture-0410; Fixture-0430; Screw-0114; Screw hole-0115; Adhesive-0155; Dust cover-112, 212, 312 ... 912.

Best Mode of the Invention

The invention will be further described below with reference to the drawings.

Fig. 1 shows a longitudinal sectional view of the first embodiment of the speaker. The speaker is composed of a lower yoke 111, a permanent magnet 102, an upper yoke 101, a columnar core 103, a dust cover 112, a basin frame 105, a diaphragm 166, a blank holder (not shown), and a fixed core support 1 18 , Voice coil 120, ring magnetic gap 110 and so on. The upper yoke 101 is a flat plate made of a circular, rectangular, or regular polygonal magnetic material. A central hole is provided with a shaft hole 126. The shaft hole 126 is generally a round hole, and may also be a cylindrical pole core 103. Matching square or regular hexagonal holes. The lower yoke 111 is an indented flat plate made of a good magnetically conductive material having a circular or rectangular or regular polygonal area equivalent to the projected area of the upper yoke 101. A convex pole piece 129 is provided at the peripheral portion of the flat plate. The equivalent magnetic resistance of the small lower yoke and the magnetic leakage between the upper and lower yokes are in accordance with the technical characteristics of a rare earth permanent magnet. transition. A columnar pole core 103 is also provided at the central portion of the concave bottom plate of the lower yoke 111, which has a circular or square or regular hexagonal solid or hollow cross-sectional shape, and its upper end projects into the In the central shaft hole 126 of the upper yoke 101, the inner profile of this hole and the vertical outer profile 130 of the columnar pole core 103 form the annular magnetic gap 110 of the speaker. In order to simplify the production process and reduce the magnetic resistance, the columnar shape The pole core 103 may be integrated during the lower yoke 111 casting, tire die forging, and cold heading. In order to reduce the air damping during the axial movement of the voice coil and improve the heat dissipation effect of the voice coil, two or more concave convection air holes uniformly distributed on the peripheral pole shoes of the lower yoke 111 may be provided. The inner bottom surface of the concave flat plate of the yoke is flat. A ring-shaped or more than one fan-shaped or bar-shaped rare-earth permanent magnet 102 is provided at the peripheral part between the upper yoke 101 and the pole shoe 129 of the lower yoke 111, which are usually made of neodymium iron boron flakes. It is constituted and is magnetically polarized in the thickness direction. The upper yoke, the lower yoke, and the permanent magnets can be bonded into a whole by an adhesive in a conventional manner, thereby forming a magnetic driver of the loudspeaker. 伹 Another method of preparation provided by the present invention can also be adopted: Several through holes 106 on the upper yoke plane, several screw holes 107 evenly distributed on the lower yoke plane, and fasteners 0109 made of non-magnetic materials. The magnetic driver is assembled into a whole by a combination method. For details, see FIG. 14 and the like are described below. A platform surface 103 is also provided on the outer plane of the upper yoke 101, and a screw hole 0115 is provided on the upper yoke 101. The speaker bracket is fixed on the upper yoke with screws 0114. In addition, screw holes can also be provided on the vertical surface of the outer yoke 101 for mounting the basin frame 105 (not shown in Fig. 1). At this time, the speaker can be equipped with a large-diameter fixed core support.

Fig. 2 is a longitudinal sectional view of a magnetic circuit according to a second embodiment of the present invention. The upper yoke 201 of the magnetic circuit is a concave or concave flat plate made of a circular or rectangular or regular polygonal magnetic material. A convex pole piece 229 is provided on the periphery of the plate. The concave bottom plates are contracted and transitioned in a fold line or an arc. The central portion of the concave bottom plate is also provided with a shaft hole 226, which is usually a circular hole, or a square or regular polygon hole matching the columnar pole core 203. The lower yoke 211 is a flat plate made of a good magnetically conductive material having a circular or regular polygonal area equivalent to the projected area of the upper yoke 201. A cylindrical pole core 203 is provided in the central part of the lower yoke, and the upper end thereof projects into the shaft hole 226. A ring magnetic gap 210 is formed with the speaker. When the lower yoke 211 is made by casting, membrane forging, or cold heading, the replacement page (the Article 26) The columnar pole core 203 can be integrally formed with it. The remaining parts are exactly the same as the description of the embodiment 1 in FIG. 1, and will not be repeated in this figure.

Fig. 3 is a longitudinal sectional view of a magnetic circuit according to a third embodiment of the present invention. The upper yoke 301 and the lower yoke 311 are each a concave flat plate made of a circular or rectangular or regular polygonal magnetic material, and their projection areas are equivalent. Otherwise, it is exactly the same as the description of the first embodiment in FIG.

Fig. 4 is a longitudinal sectional view of a magnetic circuit according to a fourth embodiment of the present invention. The upper yoke 401 is an indented flat plate, and the pole surface 400 and the inner profile surface 424 of the pole shoe and the concave bottom plate of the upper yoke are contracted and transformed in a straight line. The flat plate of the lower yoke protrudes outward from a flat surface at the central axis portion. Except for this, this embodiment is exactly the same as that shown in FIG. 1.

Fig. 5 shows a fifth sectional view of a magnetic circuit having a square yoke. Its viewing direction is equivalent to the A-A plane projection of FIG. 1. Four strip-shaped neodymium-iron-boron sheets 502 with equal area, volume, and magnetic properties are uniformly distributed at the peripheral portions between the lower yoke pole piece 529 and the upper yoke 501. The lower yoke 511 is provided with four uniformly distributed convection air holes 517 and the four evenly distributed lower yoke screw holes 507, and the upper yoke is provided with four penetration holes 506, which are equivalent to the screw holes. 4 A copper screw passes through the upper yoke 501, the structural space 563, and the permanent magnet 502, and applies a static pressure to the anastomotic pole surface 500 and couples them into a whole magnetic driver (refer to FIG. 14 and its description). No conventional adhesive is applied between all anastomotic pole faces. After the assembly is completed, four convection air holes 517 distributed on four sides can be formed at the gap at the end of the permanent magnet (refer to FIG. 17 and its description). In order to further improve the heat dissipation effect of the voice coil, the cylindrical pole core 503 has a cross-sectional shape of a hollow tube, and a central hole forms a heat dissipation hole 531. The other parts are the same as the description of the embodiment i in FIG.

Fig. 6 shows a plan view of a magnetic circuit embodiment 6 having a square yoke. The four strip-shaped neodymium-iron-boron flakes 602 coincide with each other on the sides. Four uniformly distributed upper yoke penetration holes (506 and lower yoke screw holes 607 are respectively provided on the concave bottom plates of the upper yoke 601 and the lower yoke 61 1), and the fastener 0109 is 4 copper screws. Tighten the copper screws, and apply static pressure to the anastomotic pole surface 600 and connect the upper yoke, permanent magnet, and lower yoke as a whole magnetic driver (refer to FIG. 14 and its description). The description is exactly the same.

Fig. 7 is a plan sectional view showing a magnetic circuit embodiment 7 having a rectangular yoke. Two large strip-shaped neodymium-iron-boron sheets 702 with equal area, volume, and magnetic properties are arranged on the long side of the rectangle, and two small strips with equal area, volume, and magnetic properties are arranged on the short side of the rectangle. For the shape permanent magnet 702, as long as the geometry of the permanent magnets in the longitudinal direction is appropriately selected, a uniform magnetic flux density can be obtained in the ring magnetic gap 710 of the magnetic driver after the assembly is completed (refer to FIG. 14 and its description). The remaining parts are exactly the same as the description of the first embodiment in FIG.

Fig. 8 is a plan sectional view of Embodiment 8 of a magnetic circuit having a circular yoke. The three through holes 806 and the lower yoke screw holes 807 of the upper yoke are evenly arranged on the concave bottom plates of the upper yoke 801 and the lower yoke 811, respectively. The permanent magnet 802 is a circular ring NdFeB permanent magnet. The ventilation of the voice coil is improved by the heat dissipation hole 831 provided in the central hole of the columnar core 803 (refer to FIG. 14 and its description). The rest is exactly the same as the description of the first embodiment of FIG.

Fig. 9 shows a magnetic circuit embodiment 9 with a circular yoke in a plan sectional view. The permanent magnet 902 is composed of 4 Nd-Fe-B fan-shaped sheets with equal area, volume, and magnetic properties. The ends of each magnet are left with a proper gap and form convection air holes 917 distributed on four sides (refer to FIG. 14 and its description). ), And the other parts are exactly the same as the description of Embodiment 1 in FIG. 1.

It should be noted that: the embodiments in FIGS. 5 to 9 are also applicable to any one of the three combined magnetic circuits of the present invention. They are all drawn in the A-A direction of FIG. 1.

FIG. 10 is a structural installation schematic diagram of the hollow frame 104 necessary for the speaker manufacturing method of the present invention. Hollow Box Replacement Page (Article 26) The frame 104 is a sliding guide and positioning device of a rare earth permanent magnet in a combined magnetic circuit with sufficient rigidity made of non-magnetic materials, and is usually made of engineering plastics or non-ferrous metals or phenolic materials. As shown in Fig. 10a, the hollow frame 104 is specially designed to cooperate with the above-mentioned concave-shaped yoke with arc-shaped transition connection (see Fig. 1). The geometric size of the hollow frame is designed according to the inner profile 124 of the pole shoe of the lower yoke and the concave bottom plane size of the lower yoke and the height of the pole shoe and the permanent magnet, for example, it has a degree ¾. The hollow frame 104 is embedded in the concave part of the concave-shaped magnetic yoke, and the outer contour surface 134 of the hollow frame 104 and the inner contour surface 124 of the pole shoe of the yoke are well matched and are bonded by coating therebetween. The agent 0155 adheres the hollow frame 104 to the yoke. One of its outer horizontal planes 100 ′ is equal to or slightly lower than the millimeter-level gap of the pole surface 100 of the pole shoe, and the other outer vertical plane 122 constitutes the sliding guide and positioning surface of the permanent magnet 102 to control the permanent magnet to extend out of the pole shoe. 129 has a sufficient width ΔB so that the yoke can sufficiently absorb the leakage flux of the permanent magnet. At this time, the height of the hollow frame 104 should be smaller than the other pole surface 100 of the permanent magnet 2 by a margin of Δ¾. As mentioned above, the positioning surface 122 should be coated with adhesive 0155 in advance, but it must have a sufficiently long curing time so that all permanent magnets can be fixed in place after they are installed in place. FIG. 10b shows a schematic plan view of the structure of a square hollow frame 104; FIG. 10c shows a schematic plan view of the structure of a circular hollow frame 104. There is no doubt that according to the different structural types of the various yokes provided by the present invention, the hollow frames 104 to 904 can be made into various corresponding geometric shapes and geometric sizes.

FIG. 11 shows a schematic plan view of a ring magnetic gap of a speaker and a longitudinal sectional view of an embodiment of a cylindrical pole core. In conjunction with Embodiment 1, FIG. 11a shows the annular magnetic gap 110 and the columnar pole core 103 having a regular cross-section regular hexagon. Compared with the circular or square cross-sectional shape, the regular hexagonal annular magnetic gap 110 formed by the regular hexagonal columnar pole core 103 and the shaft hole 126 has the longest peripheral length. Therefore, the regular hexagonal sound is embedded therein. The ring 120 will have the longest perimeter and the best heat dissipation effect, so that the electro-acoustic conversion efficiency of the speaker is relatively improved. The regular hexagonal columnar pole core can be made by the "cold drawing" process. After cutting at the specified height, the root is turned into a cylinder 130A. The diameter of the cylinder is equivalent to the diameter of the inscribed circle of the regular hexagon. A corresponding circular hole is provided on the lower yoke 111, and the cylindrical body 130A of the columnar pole core is fitted into the circular hole by interference fit. Finally, the concave circular hole D _{2 of the} base portion of the cylinder is inserted. Expansion makes the base of the cylinder concave into the inner circle, and the flange 130B expands tightly and is riveted on the lower yoke 111. The schematic diagram can be seen in Figure lib. The square pole cross-section of the columnar pole core and the annular magnetic gap can also be processed by analogy. FIG. 1k shows that when the columnar pole core 103 and the shaft hole 126 are in a regular hexagonal cross section, a short arc-shaped arc segment is provided at the top of the inner corner, and the line segment and the two sides of the inner corner are tangent to each other. Point 010, and the center of the arc segment falls exactly on the angle bisector of the inner corner. The remaining regular polygonal toroidal pole cores, toroidal magnetic gaps, and matching voice coil skeletons can be processed by analogy as described above.

FIG. 12 shows a plan view of an embodiment of a speaker manufacturing method provided by the present invention. The speaker has the structure shown in FIG. 1 and FIG. 6. The hollow frame 104 is embedded in a recessed portion of the lower yoke 111. The loudspeaker has 4 neodymium-iron-boron permanent magnet sheets with equal area, volume, thickness, and magnetic properties. As shown in FIG. 13, the lower yoke 111 is first fixed with a fixture 0410 on a suitable height and a suitable operating surface, and a thin-walled sleeve 0108 made of non-magnetic conductive material and having high rigidity is set to On the columnar pole core 103 of the lower yoke 111, the thin-walled sleeve 0108 has smooth inner and outer wall surfaces, and the inner wall surface and the vertical outer surface 130 of the columnar pole core 103 are in a sliding fit. The cross-sectional shapes between the two are mutually Matching, the wall thickness of the thin-walled sleeve 010S is the width of the annular magnetic gap 110, and there is a sliding fit between the two. A value is the replacement page (Article 26 of ⁷ ) The optimum value does not exceed a negative tolerance of ten microns. The other outer end of the thin-walled sleeve 0108 is provided with a tapered, smaller cross-sectional shape, and transitions uniformly to a nominal cross-sectional area defined by the annular magnetic gap 110 within an axial length of approximately t ten millimeters. The shaft hole 126 of the upper yoke 101 is easily inserted into the thin-walled sleeve 0108 from the outer end of the thin-walled sleeve 0108 and slides inward in the direction indicated by the arrow in FIG. 13. After reaching a certain height, it is clamped by 0430. It is clamped and positioned by the auxiliary device (not shown). At this time, there is a pole surface gap Η ₂ ′ between the pole surface 100 of the upper yoke 101 and the pole surface 100 of the lower yoke pole shoe 129, which is a little higher than the thickness Η _{2 of the} NdFeB permanent magnet sheet. The optimal installation clearance is less than tens of microns. The first neodymium-iron-boron permanent magnet sheet 102a that has been saturated on the magnetizer is inserted into the gap between the pole faces from the outside in the direction of the arrow shown in FIG. 12a and slides to the installation position, as shown in FIG. 12b. The second permanent magnet 102b is also inserted into place in the direction of the arrow shown in FIG. 12b, thereby forming a symmetrical combined transition magnetic circuit. At this time, four copper screws 0109 can be inserted into the upper magnetic penetrating hole 106 and screwed into the screw holes 107 of the lower yoke (see FIG. 14). Fig. 12c shows the pushing direction of the three permanent magnets in place and the last permanent magnet 102d. After all 4 permanent magnets are installed in place (as shown in Figure 6), you can remove the upper yoke clamp 0430, tighten the copper screws, and finally remove the thin-walled sleeve 0108 and the lower yoke clamp 0410, which are to be pre-coated on the hollow frame After the adhesive on 104 is cured, an integrated magnetic drive is obtained.

The clamp 0410 and the clamp 0430 can be simple clamps similar to a bench vise or a three-jaw chuck and a four-jaw chuck. It has a flexible device for tightening the inside and relaxing it outwards. Of course, it can also be further designed to be automatic Special fixture on the assembly line. Among them, the fixture 0430 is also provided with a linkage lever system 0431 capable of axial displacement, and the system is further provided with an auxiliary positioning device 0432 (not shown in Fig. 13), such as a vertical positioning mechanism of a bench-type drilling machine or a vertical drilling machine for Limit or fine-tune the pole surface gap ¾ 'between the upper yoke 101 and the pole shoe 129 to a predetermined value. Sometimes, for simplicity and accuracy, the auxiliary positioning device 0432 may also be one or two movable plug gauge blocks with an axial height Η ₂ '. When the clamp 0430 moves the upper yoke inwardly under the driving of the linkage lever system 0431, the movable plug gauge block is placed in the pole gap Η ₂ ′ in advance and the upper magnetic yoke is thereby used. The yoke is positioned, and the magnetic circuit can be combined after removing the plug gauge block.

14 shows a longitudinal sectional view of a method for manufacturing a speaker and a method for manufacturing a magnetic driver sheath. According to the foregoing description, the three types of structures provided by the present invention (see FIG. 1, FIG. 2, and FIG. 3 and their descriptions), the yoke and the magnet can be combined into one with an adhesive in a conventional manner. For the overall magnetic circuit, 伹 may also be implemented by using another method for preparing a loudspeaker provided by the present invention, that is, implemented in a manner shown in FIG. 13. Taking the structure of FIG. 1 as an example, FIG. 14 further supplements the description of FIG. 13: On the mounting plane of the upper yoke 101, the axis of the pole core 103 is used as the axis of symmetry, and more than three uniformly arranged On the mounting plane of the lower yoke 111, three or more uniformly distributed screw holes 107 corresponding to the through holes 106 are provided on the axis of the cylindrical pole core 103 as the axis of symmetry. A hollow frame 104 is pre-embedded and installed in the concave space of the lower yoke and adhered firmly in advance by an adhesive. The outer vertical surface 122 of the hollow frame is pre-coated with an adhesive 0155, and the entire speaker magnetic circuit is explained in accordance with Figs. 12 and 13 After the provided method is installed in place, fasteners (such as copper screws, bolts, rivets, and the like) made of non-magnetic conductive material are inserted into the penetration hole 106, and the fasteners are tightened one by one, and the yoke is aligned. Two anastomotic pole surfaces 100 consisting of a permanent magnet, a lower magnet yoke, and the like apply static pressure. After the adhesive 0155 coated between the inner surface of the permanent magnet 102 and the positioning surface 122 of the hollow frame 104 is cured, a No longer painted between the permanent pole and the yoke anastomosis pole surface Binder, thus the reluctance of the magnetic circuit of the speaker less novel magnetic drive. Alternatively pages (^ Section 26) Since rare earth permanent magnets such as neodymium-iron-boron permanent magnets have high Br values and maximum magnetic energy products, the magnetic field gradient of the leakage magnetic flux on the outer vertical plane of the speaker magnetic driver obtained in the manner described above is relatively high, and it is easy to ferromagnetically The substance is attracted to the surface of the driver and the magnetic flux density in the ring gap of the speaker is reduced. In addition, rare-earth permanent magnets such as neodymium-iron-boron are very brittle and are easily damaged by mechanical impact when exposed. In order to overcome the above two shortcomings and further strengthen the overall combined strength of the combined magnetic circuit of the speaker, the present invention uses two or more sections of magnetic driver jackets made of non-magnetically conductive material, along the upper yoke 101, the lower yoke 111, and the permanent magnet 102. The vertical outer profile (taking FIG. 1 as an example) tightly wraps the magnetic circuit inside. The sheath B7 is pressure-molded by plastic in this embodiment. The inner contour surface 138 of the sheath 137 is provided with a groove 139 matching the permanent magnet 102. The inner contour surfaces 138 and 139 or the vertical outer contour surface of the magnetic circuit are pre-coated with an adhesive 0155. The static pressure F _in is applied to the sheath 137 from the outside to the inside by the clamp as shown in the arrow direction of FIG. 15. In addition, the bonding surface of each section of the sheath is also pre-coated with an adhesive and squeezed with a force F _in . After curing, the clamp is removed, and a new type of magnetic actuator with higher combined strength is obtained. There is no doubt that a magnetic driver jacket with the same effect can also be prepared by providing a penetrating hole or a screw hole in the sheath 137, and using a plurality of fasteners made of non-magnetic conductive material. Since this is a well-known technology in the scope of common sense, the present invention does not draw the drawings and further description thereof.

Fig. 15a shows a plan sectional view of Embodiment 1 of a speaker magnetic driver sheath according to the present invention. It has a circular yoke. Referring to FIG. 1 and FIG. 14 and the description, FIG. 15 a is a plan sectional view with AA direction. In this embodiment, the sheath 137 is composed of two semicircular arc-shaped segments. In order to cooperate with the magnetic circuit structure type shown in FIG. 9 to improve the ventilation and heat dissipation effect of the speaker, two ventilation openings 140 can also be provided on each section of the sheath 137, as shown in FIG. 15b. Adhesive 0155 is also applied to the bonding surface of the two-stage sheath. The arrow F _in indicates the direction in which static pressure is applied to the jig and the magnetic actuator.

Fig. 16a shows a plan sectional view of a magnetic actuator sheath embodiment 2. It has a square yoke. It has a magnetic circuit structure type shown in FIG. 5. The sheath 237 of this embodiment is composed of a four-striped sheath. Adhesive is applied to the inner contour surface of the sheath and the joint surface of the adjacent sections of sheaths. The arrow F _in indicates the direction in which static pressure is applied to the clamp and the magnetic driver. In order to improve the ventilation and heat dissipation effect of the speaker, an air vent 240 can also be provided on each sheath, as shown in Figure 16b.

Fig. 17 shows a longitudinal sectional view (node) of an embodiment of a speaker reciprocating convection ventilation. This is a unique ventilation and cooling method provided by the present invention. It can be seen from the figure that the lower yoke 111 is a typical concave concave flat plate, and the peripheral pole shoes are provided with two or more concave concave convection air holes 117 evenly distributed. Corresponding vents 164 and vents 140 are also provided on the hollow frame 104 and the magnetic driver jacket 137, respectively. When the diaphragm and fixed core support of the speaker (not shown in this figure) are reciprocated during operation, For example, when the diaphragm and the core support are moved upward (outside), the air on the left side of the reciprocating convection airway becomes thinner. Space beyond the road. When the diaphragm and the core support move downward (inside), the air on the left side of the convection airway (including the annular magnetic gap) becomes denser, and the cold air enters the airway through the peripheral gap of the basin frame and the annular magnetic gap and passes through the ventilation. The ports 164, 117 and the sheath vent 140 are exhausted to a space outside the magnetic circuit. As long as the speaker is working, the heat of the voice coil will be taken away by the above-mentioned reciprocating airflow, thereby achieving a good ventilation and cooling effect.

FIG. 18 shows a longitudinal sectional view (node) of an embodiment of a method for adjusting a magnetic field strength of a ring gap. On the concave flat plate of the lower yoke 111 or the position of the lower yoke of the concave air hole of the peripheral pole shoe (see FIG. 1 and its description), the axis of the columnar pole core 103 is symmetrical The shaft is provided with several uniformly distributed axial screw holes 1003, and the screw holes are screwed into the replacement page (Article 26) Section screw 1002, whose inner front end has a regular machined outer surface, such as a conical or circular truncated shape, and its outer end is provided with a concave operating surface, such as a well-known form such as a flat or cross shape, and a square shape. . The adjusting screw 1002 is usually made of a ferromagnetic material, but its projection position should fall into the structural space 163 outside the projection plane of the voice coil. After the speaker magnetic driver provided by the present invention is assembled, the depth of entry of the adjustment screw 1002 or the replacement of the adjustment screw 1002 of different lengths can be used to control the horizontal profile of the front end of the adjustment screw and the upper yoke 113 or the permanent The leakage magnetic flux between the S poles of the magnet 102: The rotation depth of the adjustment screw 1002 increases the leakage magnetic flux 1001, and the magnetic field strength at the annular magnetic gap 110 adjacent to the adjustment screw is thus (or the magnetic flux density). reduce. Conversely, when the adjusting screw 1002 is rotated outward, the leakage magnetic flux 1001 decreases, and the magnetic field strength (or magnetic flux density) at the annular magnetic gap 110 adjacent to the adjusting screw increases. Adjusting the adjusting screws distributed around the annular magnetic gap one by one can control the uniformity of the magnetic density in the annular magnetic gap or raise and lower the magnetic field strength in the annular magnetic gap as a whole, thereby ensuring that speakers of the same specification have The same magnetic field strength can eliminate the dispersion of different batches of loudspeaker products of the same specification, or improve the distortion of the loudspeaker caused by the uneven magnetic gap magnetic field.

FIG. 19 is a plan view showing an embodiment of a method for adjusting the intensity of a magnetic field of a ring gap. As can be seen from the figure, a circular yoke is used in this embodiment. Four adjusting screws 1002 are arranged on a concentric circumferential line of the lower yoke 111, and the circumferential angle of any two adjusting screws is 90 °. In order to enhance the adjustment sensitivity, the number of adjustment screws should be increased as much as possible, but a too close adjustment screw hole 1003 will increase the equivalent magnetic resistance of the lower yoke. Therefore, due consideration should be given to the above two factors. At the same time, in order to minimize the leakage magnetic flux that may be caused by the operating screw end (outside) of the adjustment screw, the outer portion of the adjustment screw hole 1003 can be expanded into a countersunk hole, so that the outer end of the adjustment screw 1002 can sink into the lower magnetic field. The outer surface of the yoke 111 is within.

Industrial applicability

The speaker implemented according to the present invention has the following advantages:

1. The magnetic resistance of the magnetic circuit is reduced, and the magnetic energy product of the rare earth permanent magnet is utilized to the maximum.

2. High sensitivity. In the case where the size of the speaker, the software material, and the main electro-acoustic indicators are equivalent, the efficiency is improved by more than 2 to 4 times than that of the conventional speaker.

3. The voice coil rises at a low temperature, and the work is highly reliable. From improving the sensitivity and reducing the input power, it has fundamentally solved the disadvantages of high temperature rise of the voice coils of Hi-Fi speakers and professional speakers, the "power compression" problem caused by continuous work, and the technical problems of easily burning the voice coils.

4. After the speaker magnetic driver or the entire speaker assembly is completed, the sensitivity of the speaker and the magnetic field unevenness of the annular magnetic gap can be adjusted to effectively control the dispersion of the batch product and improve the distortion.

5. It is a green product that saves energy, reduces consumption, and is cost-effective. It can comprehensively replace traditional speakers.

Replacement page (^ Article 26)

Claims

Rights request

1. A loudspeaker, which mainly includes a permanent magnet, a voice coil, a fixed core support, a diaphragm, a basin frame, and a set of magnetic circuits with a ring-shaped magnetic gap, which are characterized by:

a. The upper yoke of the magnetic circuit is a flat plate made of magnetic material. The central part is provided with a shaft hole. It is usually a round hole or a square or a regular hexagon that matches the lower yoke cylindrical pole core. Shaped hole

b. The lower yoke of the magnetic circuit is an indented flat plate made of magnetic material equivalent to the projected area of the upper yoke. A convex pole shoe is provided at the peripheral part of the flat plate, and a central part of the concave flat plate is provided. A cylindrical pole core with a circular or square or regular hexagonal solid or hollow cross-sectional shape, the upper end of which extends into the central shaft hole of the upper yoke and is higher than the outer plane of the upper yoke A height Δ necessary to form a fully symmetrical magnetic circuit, the value of which is several millimeters to tens of millimeters;

c At the peripheral portion between the upper yoke and the pole shoe of the lower yoke, there is provided a ring-shaped or more than one fan-shaped or strip-shaped rare earth permanent magnet sheet of uniform thickness, They are all magnetically polarized in the thickness direction; d. The voice coil matches the shaft hole and the columnar pole core, and its optimal cross-sectional shape is a regular hexagon, and the top of the inner corner of each hexagon is set A short arc-shaped line segment is tangent to both sides of the inner angle, and the center of the circle lies on the angle bisector of the inner angle;

e. On the peripheral pole shoes of the lower yoke, two or more uniformly-concave convection air holes can also be provided. When the bottom of the air hole is deepest, it is flush with the inner bottom surface of the concave flat plate of the yoke. .

2. The loudspeaker according to claim 1, characterized in that: the upper yoke is a circular flat plate, and the lower yoke is a circular concave flat plate.

3. The loudspeaker according to claim 1, wherein: the upper yoke is a regular polygonal flat plate, and the lower yoke is a regular polygonal concave flat plate.

4. The loudspeaker according to claim 1, wherein: the upper yoke is a rectangular flat plate, and the lower yoke is a rectangular inner concave flat plate.

5. A loudspeaker, which mainly includes a permanent magnet, a voice coil, a fixed core support, a diaphragm, a basin frame and a set of magnetic circuits with a ring-shaped magnetic gap, which are characterized by:

a. The upper yoke of the magnetic circuit is an indented flat plate made of magnetic material. A convex pole shoe is provided at the peripheral portion of the flat plate. A shaft hole is provided at the central portion of the concave flat plate. The circular hole may also be a square or regular hexagon hole matching the lower yoke cylindrical pole core;

b. The lower yoke of the magnetic circuit is a flat plate made of magnetic material that is equivalent to the projected area of the upper yoke. The central part is provided with a columnar pole core and a solid or circular or square or regular hexagon. A hollow cross-sectional shape, the upper end of which extends into the central shaft hole of the upper yoke and is higher than the outer plane of the upper yoke by a height necessary to form a fully symmetrical magnetic circuit; the value is several millimeters to tens of millimeters;

c At the peripheral portion between the upper yoke and the pole piece of the lower yoke, a ring-shaped or more than one fan-shaped or strip-shaped rare earth permanent magnet sheet uniformly distributed and uniformly provided , They are all magnetically polarized in the thickness direction; replacement page (^ Article ²⁶ ) d. The voice coil is matched with the shaft hole and the cylindrical pole core, and its optimal cross-sectional shape is a regular hexagon, and a short circular arc segment is provided at the top of the inner corner of each hexagon. The line segment is tangent to both sides of the inner angle, and the center of the circle lies on the angle bisector of the inner angle;

e. On the peripheral pole shoes of the upper yoke, more than two uniformly-concave convection air holes can be provided. When the bottom of the air hole is the deepest, it is flush with the inner bottom surface of the concave flat plate of the yoke. .

6. The loudspeaker according to claim 5, wherein: the upper yoke is a circular indented flat plate, and the lower yoke is a circular flat plate.

7. The loudspeaker according to claim 5, wherein: the upper yoke is a regular polygonal flat plate, and the lower yoke is a regular polygonal flat plate.

8. The loudspeaker according to claim 5, wherein: the upper yoke is a rectangular indented flat plate, and the lower yoke is a rectangular flat plate.

9. A loudspeaker, which mainly includes a permanent magnet, a voice coil, a fixed core support, a diaphragm, a basin frame and a set of magnetic circuits with a ring-shaped magnetic gap, which are characterized by:

a. The upper yoke of the magnetic circuit is an indented flat plate made of magnetic material. The peripheral part of the flat plate is provided with convex pole shoes. The central part of the concave flat plate is provided with a shaft hole, which is usually a round hole. It can also be a square or regular hexagonal hole that matches the cylindrical core of the lower yoke;

b. The lower yoke of the magnetic circuit is an inner concave flat plate made of magnetic material equivalent to the projected area of the upper yoke. A convex pole shoe is arranged at the peripheral part of the flat plate, and the central part of the concave flat plate A cylindrical pole core is provided with a solid or hollow cross-sectional shape having a circular or square or regular hexagon shape, the upper end of which extends into the central shaft hole of the upper yoke and is higher than the outer plane of the upper yoke A height Δ necessary to form a fully symmetrical magnetic circuit, the value of which is several millimeters to tens of millimeters;

c At the edge portion between the upper yoke and the pole shoe of the lower yoke, a ring-shaped or more than one fan-shaped or strip-shaped rare-earth permanent magnet sheet uniformly distributed and uniform in thickness is provided. , They are both magnetically polarized in the thickness direction; d. The voice coil matches the shaft hole and the cylindrical pole core, and the best cross-sectional shape is a regular hexagon, and the top of the inner corner of each hexagon is A short arc-shaped line segment is provided, the line segment is tangent to the two sides of the inner corner, and the center of the circle falls on the angle bisector of the inner corner;

e. On the peripheral pole shoes of the upper yoke and the lower yoke, two or more uniformly-concave convection air holes can be provided. When the bottom of the air hole is the deepest, it is the same as that of the inner flat plate of the yoke. The bottom surface is flat.

10. The loudspeaker according to claim 9, characterized in that each of said upper yoke and said lower yoke is a circular concave flat plate.

11. The loudspeaker according to claim 9, characterized in that each of said upper yoke and said lower yoke is a regular polygonal concave flat plate.

12. The loudspeaker according to claim 9, wherein: said upper yoke and said lower yoke are each a rectangular indented flat plate.

13. A method for preparing a loudspeaker as specified in claims 1, 5, and 9, characterized in that: a replacement page (^ ² Article 26) a. A hollow frame made of a non-magnetically permeable material with sufficient rigidity is embedded in the concave space of the upper yoke or the lower yoke, and the outer contour surface of the embedded part and the inner contour of the yoke The surfaces are well matched and pre-adhered firmly. The outer horizontal plane of the hollow frame is equal to or slightly lower than the millimeter gap of the pole surface of the pole shoes around the yoke. A sliding guide and a positioning surface of the permanent magnet sheet; in addition, at the appropriate height of the outer vertical surface, two or more vents uniformly distributed in the peripheral direction may be provided;

b. A thin-walled sleeve made of a non-magnetically permeable material with sufficient rigidity, has smooth inner and outer wall surfaces, and its cross-sectional shape is the same as the axial hole of the upper yoke and the columnar shape of the lower yoke The pole cores are matched with each other, and one end of the thin-walled sleeve is sleeved on the columnar pole core, and the other end thereof has a tapered smaller cross-sectional shape, so that the upper yoke can be easily fitted into The thin-walled casing;

c The inner wall surface of the thin-walled sleeve is in a sliding fit with the vertical outer profile of the lower yoke cylindrical pole core, and the outer wall surface of the thin-walled sleeve and the inner surface of the shaft hole of the upper yoke The profile is a sliding fit, and the optimal value of the sliding fit gap does not exceed ten microns;

d. Fix the upper yoke and the lower yoke on two parallel ice planes by using two pairs of clamps and operate one of the clamps to make the upper yoke from the outside to the thin-walled sleeve. Slide inside, use an auxiliary positioning device or plug gauge block to terminate the sliding stroke of the upper yoke and ensure that the gap between the pole surface of the upper yoke and the lower yoke is slightly smaller than the thickness of the permanent magnet sheet Installation gap, its optimal value does not exceed tens of microns;

e. inserting more than one piece of a rare earth permanent magnet sheet of equal thickness that has been pre-saturated into the polar surface gap of the yoke from the outside according to the prescribed polarity and sliding it to the position limited by the positioning surface of the hollow frame;

f. Insert fasteners made of non-magnetically conductive material into three or more uniformly distributed ^ fastening holes on the mounting surface of the upper yoke and the lower yoke, and remove them after all permanent magnets are installed in place. The upper yoke clamp and the auxiliary positioning device or the plug gauge block are tightened to apply static pressure to the anastomotic pole surfaces of the yoke and the permanent magnet, and are to be coated in advance on the positioning surface of the hollow frame or After the adhesive on the horizontal plane is cured, remove the thin-walled sleeve and the lower yoke clamp;

g. An adhesive may be applied to the outer joints of the upper pole yoke and the outer pole joints of the anastomosis pole surfaces of the permanent magnet and the permanent magnet to increase the connection strength.

14. A method for preparing a speaker magnetic driver jacket according to claims 1, 5, 9, and 13, characterized in that:

a. Two or more sections of a sheath made of non-magnetic material are used to tightly wrap the upper yoke, the lower yoke and the vertical outer surface of the permanent magnet;

b. The inner profile of the sheath and the vertical outer profile of the upper yoke, the lower yoke and the permanent magnet are mutually matched, and a cement is pre-coated before assembly;

c. The bonding surface between the two or more sections of the sheath is also pre-coated with adhesive;

d. Applying static pressure to the shroud sleeve in the assembly from the outside to the inside by means of a clamp or tightly pressing the sheath against the upper yoke, through a fastener provided between adjacent sections of the sheath. The vertical outer contours of the lower yoke and the permanent magnet are also extruded, and the clamp is removed after the adhesive is cured. Replacement page (Article 26)

15. A method for adjusting the magnetic field strength of a ring magnetic gap of a loudspeaker according to claims 1, 5, 9, and 13, characterized in that:

a. On the concave flat plate of the lower yoke or at the position of the lower yoke of the concave air hole of the peripheral pole shoe, more than two adjusting screws are uniformly arranged along the axis of the columnar pole core. Hole

b. The corresponding adjusting screw made of magnetically permeable material is screwed into the adjusting screw hole from the outside to the inside, and the front end of the adjusting screw has a regular machined outer surface;

c The adjusting screws are all arranged on the outside of the voice coil, and the outer ends of the adjusting screws can also sink into the adjusting screw holes;

d. adjusting the penetration depth of the adjusting screw or replacing the adjusting screws of different lengths, the magnetic flux leakage between the end of the adjusting screw and the upper yoke or the permanent magnet can be changed, thereby achieving adjustment Purpose of the magnetic field strength of the ring magnetic gap of the speaker.

(Replacement Article 26)