CN215010702U - Loudspeaker - Google Patents

Abstract

A speaker (1) includes a diaphragm (2), a voice coil (3) attached to the diaphragm (2), a middle magnet (4), and a frame (5), the frame (5) including an outer frame portion (6) made of epoxy resin mixed with magnetic powder and supporting the diaphragm (2), and an inner frame portion (7) supporting the middle magnet (4).

Description

Loudspeaker

Technical Field

The utility model relates to a novel speaker design for consumer products.

Background

Consumer products, such as laptops and mobile phones, are often equipped with one or more speakers, also known as electroacoustic transducers. Typically, each speaker is mounted in a very limited space inside the product. Improved audio quality is advantageous because it is preferred by consumers.

One basic form of loudspeaker is a so-called single magnet transducer. The single magnet transducer includes a single magnet and a voice coil coupled to the magnet.

Another form of loudspeaker is the so-called multi-magnet transducer, which comprises a plurality of magnets and a voice coil cooperating with the magnets. Due to the provision of a plurality of magnets, the multi-magnet transducer is able to provide a stronger magnetic field, thus enabling a higher audio quality than a single magnet transducer. However, the limited space typically available in consumer products limits the space available for mounting multiple magnets, thereby limiting the audio quality that can be achieved within given space constraints.

CN209046871U discloses a loudspeaker comprising a frame made by injection molding a composition containing magnetic powder. After molding, the frame is magnetized such that the frame forms a portion of a magnetic structure that cooperates with the voice coil.

It is an object of the invention to mitigate the above mentioned drawbacks and to provide a further improved audio quality for a given loudspeaker size.

SUMMERY OF THE UTILITY MODEL

According to a first aspect of the invention, the object is achieved by a loudspeaker. The speaker includes a diaphragm, a voice coil attached to the diaphragm, a middle magnet, and a frame including an outer frame portion made of an epoxy-based magnetic powder composite and supporting the diaphragm, and an inner frame portion supporting the middle magnet. The epoxy resin-based magnetic powder composite material is prepared by mixing epoxy resin and magnetic powder. By making at least the outer frame part of the frame from epoxy-bonded magnetic powder, the frame can be more easily designed into complex shapes according to the requirements of the consumer product to be mounted, while also enabling a more compact design of the loudspeaker, since the frame acts as a magnet (side magnet), thereby alleviating the need for additional side magnets. This generally allows the Sound Pressure Level (SPL) to be increased for a given speaker size by increasing the BL value, which is the product of the magnetic field strength (B) of the voice coil magnetic gap and the voice coil wire length (L).

At least a portion of the frame may be injection molded. For example, the outer frame portion may be injection molded. Injection molding at least a portion of the frame allows for efficient manufacture of speakers with complex geometries and tight tolerances.

The magnetic powder may be NdFeB. NdFeB is a material to which a strong magnetic field can be applied, and thus enables an increase in sound pressure level compared to the use of other materials having a weaker magnetic field.

The loudspeaker may further include a first plate disposed on top of the middle magnet. The provision of the first pole plate on top of the middle magnet enables the magnetic flux to be concentrated, thereby achieving a higher sound pressure level.

The inner frame portion may serve as a second pole plate that is attached to the bottom surface of the middle magnet and that is attached to or integral with the outer frame portion. Providing an inner frame portion at the bottom of the middle magnet, which serves as a second pole plate, enables concentration of magnetic flux, thereby achieving a higher sound pressure level.

Further, the speaker may include a third plate disposed around the voice coil, wherein the third plate is attached to the frame. The provision of a third pole plate around the voice coil enables the magnetic flux to be concentrated, thereby achieving a higher sound pressure level.

The third plate may be disposed between the outer frame portion and the inner frame portion. By providing a third plate between the outer and inner parts of the frame, the diaphragm is separated from the third plate by the outer part of the frame, which is magnetic, so that a further portion of magnetic material is provided outside the third plate. This additional portion of magnetic material increases the sound pressure level of the speaker.

The third plate may be at least partially sandwiched between the outer frame portion and the inner frame portion.

By sandwiching the third plate between the outer frame part and the inner frame part, the size of the third plate can be increased without increasing the frame size.

The third plate may divide the frame into two parts.

Drawings

Fig. 1 shows a cross-sectional side view of a loudspeaker according to a first embodiment of the invention.

Fig. 2 shows a cross-sectional side view of a loudspeaker according to a second embodiment of the invention, similar to that of fig. 1, but with the inner frame part serving as the second plate.

Fig. 3 shows a cross-sectional side view of a loudspeaker according to a third embodiment of the invention, similar to that in fig. 2, but further comprising a third plate attached to the frame.

Fig. 4 shows a cross-sectional side view of a loudspeaker according to a fourth embodiment of the invention, similar to that of fig. 3, but with the third plate sandwiched within the frame.

Detailed Description

Four different embodiments of the loudspeaker will be described below with reference to the drawings.

Fig. 1 illustrates a first embodiment of a loudspeaker 1 in cross-section. The loudspeaker 1 comprises a diaphragm 2 attached to a voice coil 3. The loudspeaker further comprises a central magnet 4 and a frame 5, the frame 5 comprising an outer frame part 6 supporting the diaphragm 2 and an inner frame part 7 supporting the central magnet 4. The diaphragm 2 is attached to the outer frame part 6 by resilient suspension means, commonly referred to as a "surround", so that the diaphragm 2 can be moved back and forth relative to the outer frame part 6 to generate sound. At least a part of the frame 5, for example the outer frame part 6, is made of a mixture of epoxy resin and magnetic powder. The material of such a frame 5 may be magnetised to control the magnetic field(s) around the voice coil 3 from the inner frame portion 7 through the middle magnet 4 to the outer frame portion 6. In this embodiment, the loudspeaker 1 comprises an optional first pole plate 8 arranged on the central magnet 4. The first plate 8 is made of a ferrous material, but in other embodiments may be made of any other suitable material.

Here, the magnetic powder chosen is NdFeB, since it enables the formation of a very strong magnetic field. However, in other embodiments, some other suitable magnetic powder may alternatively be used.

The frame 5 is injection molded directly onto the central magnet 4. However, in other embodiments, the frame 5 may alternatively be joined with other components of the loudspeaker 1 by an adhesive.

Fig. 2 illustrates a second embodiment of the loudspeaker 1 in cross-section. In the present embodiment, the inner frame portion 7 may serve as a second pole plate 9, the second pole plate 9 being attached to the bottom surface of the middle magnet 4 and attached to the frame 5 or integrated with the frame 5. According to the second embodiment, the material used for the inner frame part 7 of the second pole plate 9 may be the same as the material of the first pole plate 8, i.e. the inner frame part 7 used for the second pole plate 9 may be made of a ferrous material, but in other embodiments may be made of any other suitable material. In other embodiments, the material used for the inner frame part 7 of the second pole plate 9 may also be the same as the outer frame part 6.

Fig. 3 illustrates a third embodiment of the loudspeaker 1 in cross-section. The loudspeaker 1 according to the third embodiment further comprises a third pole plate 10 arranged around the voice coil 3, said third pole plate 10 being attached to the frame 5 (e.g. the outer frame part 6). As illustrated in fig. 3, the third plate 10 is provided on a support in the frame 5, but the third plate 10 may be arranged in other ways as long as it is in contact with the frame 5. The third pole plate 10 may also be arranged between the outer frame part 6 and the inner frame part 7, i.e. the second pole plate 9. For example, the third pole plate 10 may be at least partially sandwiched between the outer frame part 6 and the inner frame part 7 (i.e. the second pole plate 9). The third plate 10 may be aligned with the first plate 8 as shown. The third plate 10 may be made of the same material as the first plate 8, for example, may be made of a ferrous material, but in other embodiments may be made of any other suitable material.

Fig. 4 illustrates a fourth embodiment of the loudspeaker 1 in cross-section. A loudspeaker 1 according to a fourth embodiment is shown in fig. 4. This speaker 1 differs from the speaker 1 of the third embodiment in that the third plate 10 is sandwiched in the frame 5 to divide the frame 5 into two parts. Here, the outer side of the third pole plate 10 may be flush with the outer side of the frame 5, and the third pole plate 10 divides the magnetic material of the frame 5 into two parts. For example, the third plate 10 may divide the magnetic material of the outer frame portion 6 into an outer/upper frame portion 61 and an inner/lower frame portion 62. The outer/upper frame portion 61 may be made of epoxy resin mixed with magnetic powder. The inner/lower frame part 62 may be made of epoxy mixed with magnetic powder, such as NdFeB powder (e.g. the same material as the outer/upper frame part 61), or may also be made of NdFeB (e.g. the same material as the middle magnet 4).

The following table is a table of reference numerals used in the drawings.

Claims (9)

1. A loudspeaker (1), characterized by comprising: a diaphragm (2), a voice coil (3) attached to the diaphragm (2), a middle magnet (4), and a frame (5), the frame (5) comprising an outer frame portion (6) made of an epoxy resin-based magnetic powder composite material and supporting the diaphragm (2), and an inner frame portion (7) supporting the middle magnet (4).

2. A loudspeaker (1) according to claim 1, wherein at least a part of the frame (5) is injection moulded.

3. A loudspeaker (1) according to claim 1 or 2, characterized in that the magnetic powder is NdFeB.

4. A loudspeaker (1) according to claim 1 or 2, further comprising a first pole plate (8) arranged on top of the central magnet (4).

5. A loudspeaker (1) according to claim 1 or 2, characterized in that the inner frame part (7) serves as a second pole plate (9), the second pole plate (9) being attached to the bottom surface of the central magnet (4), and the second pole plate (9) being attached to the outer frame part (6) or being integral with the outer frame part (6).

6. A loudspeaker (1) according to claim 5, further comprising a third plate (10) arranged around the voice coil (3), wherein the third plate (10) is attached to the frame (5).

7. A loudspeaker (1) according to claim 6, wherein the third plate (10) is arranged between an outer frame part (6) and an inner frame part (7).

8. A loudspeaker (1) according to claim 7, wherein the third plate (10) is at least partially sandwiched between an outer frame part (6) and an inner frame part (7).

9. A loudspeaker (1) according to claim 6, wherein the third plate (10) divides the frame (5) into two parts.

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