Electrodynamic driver for a flat panel loudspeaker system

Abstract

An electric driver for a flat panel speaker system having a housing in which are installed a magnetic system, a cylindrical coil fixed to a support frame, a sound-emitting membrane attached to the cylindrical coil, a system for holding the cylindrical coil within a magnetic gap, and a flexible wiring for supplying an electric signal to the cylindrical coil. The magnetic system is made to include a cylindrical permanent magnet, a ferrite ring, and a steel washer coupling the cylindrical permanent magnet and the ferrite ring into a single structure.

Description

Technical Field

[0001] This application relates to the field of loudspeaker technology, and more particularly to an electric driver for a flat panel loudspeaker system. Background Technology

[0002] The proposed technical solution involves acoustic devices. It is an electric driver for flat panel loudspeaker systems.

[0003] A variety of industrially produced electric drives for planar acoustic systems are known from the following different companies: Dayton BST , Monaco Brands such as Visatone and Mechakustik are examples. These loudspeakers are often designed to operate in the mid-to-high frequency range. Most loudspeakers rarely extend their lower cutoff frequency below 100Hz. Less common are loudspeakers that can provide an operating range of 50Hz to 10kHz within an internal, pre-built loudspeaker system. In industrially manufactured products, there are no exciters that provide audible acoustic radiation across the entire spectrum (20Hz to 20,000Hz). Therefore, commercially available motorized exciters from many manufacturers are not suitable for creating full-range planar loudspeaker systems. The frequency range of such exciters necessitates various measures to ensure an extension of the frequency range of the acoustic system: for example, creating multi-band systems, using additional acoustic links (including complex acoustic filter systems) or additional motorized exciters to extend the lower and upper cutoff frequency ranges, these additional motorized exciters being designed to operate within a narrower upper or lower register acoustic range.

[0004] Other problems arising from the use of traditional acoustic vibration exciters in planar acoustic system design include their low electrical power. Therefore, to create high-power acoustic systems suitable for professional environments, compromises must be made: creating an assembly of several acoustic exciters within the area of ​​a diaphragm, which involves modulation amplitude distortion of the sound signal, thus degrading the acoustic quality of the loudspeaker.

[0005] It goes without saying that using such a complex and cumbersome method to solve these technical problems is impractical and would increase material costs, time costs, and labor costs.

[0006] One of the closest similar technical solutions is proposed in Russian Federation Patent No. 2456764, filed on February 10, 2012, which describes a flat panel loudspeaker. This flat panel loudspeaker is made in the form of a housing in which the following components are installed: a magnetic system, a cylindrical coil fixed to a frame, a diaphragm attached to the cylindrical coil frame, a system for holding the coil within a magnetic gap, and flexible wiring for supplying electrical signals to the coil. The disadvantages of this device are a limited operating range and low power consumption. Summary of the Invention

[0007] The technological result is an expansion of the loudspeaker's operating range.

[0008] The technical result is achieved through a broadband planar loudspeaker system with a housing containing the following components: a magnetic system, a cylindrical coil fixed to a support frame, a diaphragm attached to the cylindrical coil frame, a system for holding the cylindrical coil within a magnetic gap, and flexible wiring for supplying electrical signals to the cylindrical coil. Furthermore:

[0009] The magnetic system is fabricated to include a cylindrical permanent magnet, a ferrite ring, and a steel washer that connects the cylindrical permanent magnet and the ferrite ring into a single structure.

[0010] The cylindrical coil, fixed to the support frame, is located above the cylindrical permanent magnet and in the gap between the cylindrical permanent magnet and the ferrite ring.

[0011] The system for holding a cylindrical coil within a magnetic gap includes two centering washers of different diameters. These two centering washers are fixed at a certain distance from each other as concentric corrugated discs. The internal holes of the washers are fitted into the cylindrical coil, while the outer circumferences are fitted into the housing.

[0012] Furthermore, the flexible wiring supplying electrical signals to the cylindrical coil is stitched into one of the two centering washers and soldered to the coil terminal at one end and to the external contact group at the other end.

[0013] In some embodiments, the centering washer is made of untreated fabric or other suitable materials.

[0014] In some embodiments, the sound-generating diaphragm is attached to the cylindrical coil via an intermediate ring. Attached Figure Description

[0015] The present invention is illustrated by means of figures.

[0016] Figure 1 An overview of the proposed electric actuator is presented, along with examples of its application in a flat panel loudspeaker system;

[0017] Figure 2The disassembled electric actuator is shown;

[0018] Figure 3 An electric driver for a flat panel speaker system is shown;

[0019] Figure 4 This is a cross-sectional schematic diagram of the electric actuator;

[0020] The diagram indicates:

[0021] 1. Shell; 2. Cylindrical permanent magnet; 3. Ferrite ring; 4. Steel washer;

[0022] 5. A system that holds a cylindrical coil within a magnetic gap consists of two centering washers of different diameters;

[0023] 6. Wiring supplying electrical signals to the cylindrical coil; 7. Ring; 8. Contact element;

[0024] 9. Cylindrical coil; 10. Sound-producing diaphragm. Detailed Implementation

[0025] The proposed electric actuator for a flat panel loudspeaker system is a device that performs the following operations: converting an electrical signal from a power amplifier into mechanical energy that vibrates at a corresponding frequency; and exciting a resonant diaphragm. The application of the electric actuator in a flat panel loudspeaker system is as follows: Figure 1 As shown in the image.

[0026] like Figures 2 to 4 As shown, the electric drive consists of the following components:

[0027] Plastic housing 1 serves as a support component. A magnetic system is attached to the plastic housing 1 and holds the cylindrical coil 9 in the magnetic gap. The system is installed onto a support frame made of a series of threaded holes.

[0028] The magnetic system includes a cylindrical permanent magnet 2 (NeFeB), a ferrite ring 3 forming the outer periphery of the annular space of the magnetic system, and a steel washer 4 connecting the cylindrical permanent magnet 2 and the ferrite ring 3 together to form a single structure.

[0029] Cylindrical coil 9 is wound and fixed to a cylindrical frame made of woven phenolic plastic or other materials using copper wire;

[0030] System 5, which holds a cylindrical coil within a magnetic gap to ensure its free reciprocating motion, consists of two centering washers of different diameters, which are fixed at a certain distance from each other (in fact, the distance is 5 mm to 15 mm) and are made of untreated fabric by pressing in the form of concentric corrugated discs, wherein the internal holes are fixed to the spool and the outer periphery is fixed to the support frame.

[0031] A flexible wiring 6 that supplies electrical signals to a cylindrical coil is stitched into one of the centering washers and one end is soldered to the coil terminal and the other end is soldered to an external contact group for supplying electrical signals from an amplifier.

[0032] Ring 7 is used to secure the coil frame to the surface of the sound-generating diaphragm 10;

[0033] Contact 8 is used for supplying electrical signals.

[0034] A key feature of the exciter is the use of a ring made of ferrite material (ferrite ring) in the magnetic circuit. This material has high permeability, although its electrical conductivity is actually quite low. This property prevents the induction of Foucault current when the magnetic field lines of a moving coil intersect the thickness of the magnetic circuit material. As the amplitude of coil vibration increases, the disappearance of the back electromotive force caused by this effect results in high efficiency of the electric exciter in the lower frequency range (around tens of hertz). The higher the velocity of the magnetic field lines moving through the body of the magnetic circuit, the more pronounced the Foucault current will be, opposite to the vector of the force that produces this velocity. Therefore, if the commonly accepted steel magnetic circuit were used, the moving coil would be "stuck" in the opposite magnetic field due to its own movement in the gap. Using ferrite as the magnetic circuit material produces useful acoustic effects, such as increased efficiency, especially in the low frequency range, which in turn makes it possible to significantly extend the operating range of the device, reaching a audible lower limit of 20 Hz.

[0035] The proposed electric actuator has a composite magnetic circuit and includes three components: a cylindrical or other shaped permanent magnet 2, a steel washer 4, and a ferrite ring 3.

[0036] Using two centering washers of different diameters is a means to achieve the following technical result: a significant reduction in mechanical resonance at a certain frequency, which coincides with the self-resonance frequency of the washer. Washers with different geometric parameters and stiffness will have two different resonant excitation frequencies. As a result of this technical solution, the amplitude-frequency response diagram of a loudspeaker equipped with this type of driver exhibits smooth frequency delivery corresponding to the excitation frequency of the component with significantly reduced amplitude. Therefore, the quality of sound characteristics is improved.

[0037] The results are: loudspeakers equipped with diaphragms reproduce broad-spectrum acoustic signals; no signal filtering tools are needed; a dual-channel power amplifier is required instead of a multi-channel power amplifier; product size is reduced while maintaining consumer quality; and the objective quality control parameters of the acoustic system (amplitude-frequency diagram, spectrum-frequency amplitude analysis diagram, (spectral signal density), sound signal emission pattern, phase nonlinear distortion measurement, etc.) demonstrate significant advantages over other acoustic systems. This makes products equipped with the proposed broadband planar loudspeakers perfectly suitable for sound technologies with increasingly high demands for sound reproduction quality, including "challenging" fields such as classical concert sound systems.

Claims

1. An electric driver for a flat panel loudspeaker system, characterized in that, It includes a magnetic system and a cylindrical coil, the cylindrical coil being fixed to a support frame in the flat panel speaker system and bonded to the diaphragm in the flat panel speaker system through the support frame; The system for holding the cylindrical coil within the magnetic gap, and the flexible wiring for supplying electrical signals to the cylindrical coil; The magnetic system is fabricated to include a cylindrical permanent magnet, a ferrite ring, and a steel washer that connects the cylindrical permanent magnet and the ferrite ring into a single structure. The cylindrical coil, which is fixed to the support frame, is located above the cylindrical permanent magnet and in the gap between the cylindrical permanent magnet and the ferrite ring; The system for holding the coil within the magnetic gap includes two centering washers of different diameters, fixed at a distance from each other in the form of concentric corrugated discs, with internal holes fitted to the cylindrical coil, the cylindrical coil fitted to the support frame, and the outer peripheries of the two centering washers fitted to the housing of the flat panel speaker system. The flexible wiring supplying the electrical signal to the cylindrical coil is stitched to one of the two centering washers and soldered at one end to a coil terminal and at the other end to an external contact group. The range of the specified distance is 5mm to 15mm.

2. The electric driver for a flat panel speaker system as claimed in claim 1, characterized in that, The two centering washers are made of untreated fabric.

3. The electric driver for a flat panel speaker system as described in claim 1, characterized in that, The sound-producing diaphragm is attached to the cylindrical coil via an intermediate ring.

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