Acoustic device for launching transverse acoustic waves in a gaseous environment

Abstract

The device of the present invention includes a housing, a sound-generating diaphragm, and an acoustic vibration actuator for transverse sound waves. The housing is formed in the form of a support frame, and a rectangular sound-generating diaphragm is fixed to the support frame. The sound-generating diaphragm is formed as follows: a honeycomb layer, a surface layer bonded to the honeycomb layer from both sides, and a stable impregnation composition covering the surface layer. The acoustic vibration actuator is formed in the form of an acoustic vibration exciter, which includes a ferrite portion of a magnetic core. One end of the acoustic vibration exciter is attached to the planar sound-generating diaphragm within a dedicated line passing along the surface of the sound-generating diaphragm, the dedicated line extending from any vertex of the sound-generating diaphragm and terminating at a point on a relatively horizontal side of the sound-generating diaphragm relative to the vertex, the point being located at 2 / 3 of the distance in the horizontal direction from the relatively horizontal side.

Description

Technical Field

[0001] This invention applies to acoustics. It can be used as a loudspeaker for consumer use, the operating principle of which is based on the resonant excitation capability of bending antiphase vibrations, and then emitting transverse sound waves into the air (a wave process in which the shear vibrations of molecules are perpendicular to the direction of wave propagation). Background Technology

[0002] According to the article by SB Karavashkin and ON Karavashkina (http: / / selftrans.narod.ru / v2_1 / acoustics / acoustics03 / acoustics3rus.html) (see page 4), it is sufficient to use two antiphase emitting acoustic diaphragms as a sound source for exciting transverse waves in a gaseous environment.

[0003] Furthermore, theoretically, several devices capable of generating transverse sound waves can be distinguished according to the background of this invention. These devices include several well-known musical instruments, such as acoustic guitars, grand pianos, drums, violins, etc., in which the resonator body or diaphragm (in the case of drums) acts as a key element in forming transverse sound waves. The task of designing and manufacturing such devices is not to ensure the efficient generation of transverse wave radiation with specific signal characteristic parameters over a wide frequency range. Therefore, the ability of such devices to emit sound with transverse wave components is quite random, and it is practically impossible to adjust the radiation parameters, making such devices unsuitable for use in the technical field proposed in this invention.

[0004] The closest technical solution can be considered to be the general-purpose loudspeaker described in Russian Federation Patent No. 2692096, filed on June 21, 2019. This loudspeaker includes a diaphragm, an excitation unit, and a housing forming a cavity, within which the diaphragm and excitation unit are located. The housing has a hole on one surface, and the end of the excitation unit abuts against the end edge of the diaphragm, such that the excitation unit is excited in the same direction as the plane of the diaphragm, and the excitation unit is also rigidly mounted on the housing. The diaphragm forms a curved portion that bends from the side where the excitation unit is located to the opposite side of the other end and is positioned to cover the opening in the housing. A disadvantage of this solution is its low efficiency. Summary of the Invention

[0005] The proposed invention solves the following tasks:

[0006] • Improve the efficient operation of acoustic devices used for transverse wave radiation.

[0007] • Extends the operating frequency range to the audible limit from 20Hz to 20,000Hz.

[0008] ● Enables control over the wave generation process over a wide range, makes the device more compact compared to analog, and eliminates high-voltage components (10kV to 30kV) from the device circuitry.

[0009] ● Improve the efficiency of generating low-frequency signals with transverse acoustic components.

[0010] The technical results improve the efficient operation of acoustic devices used for transverse wave radiation, expand the operating frequency range, and increase the efficiency of generating low-frequency signals with transverse components of sound waves.

[0011] The technical result is achieved by an acoustic device for emitting transverse sound waves in a gaseous environment, the acoustic device comprising a housing, a sound-emitting diaphragm, and an acoustic vibration actuator for the transverse sound waves.

[0012] The housing is constructed in the form of a support frame, and the sound-emitting diaphragm is fixed to the support frame. The diaphragm is constructed as follows: a honeycomb layer, a surface layer bonded to the honeycomb layer, a surface layer bonded to the honeycomb structure from both sides, and a stable impregnation composition based on a polyurethane primer and varnish covering the surface layer. The acoustic vibration actuator is constructed in the form of at least one acoustic vibration exciter, the at least one acoustic vibration exciter including a ferrite portion of a magnetic circuit, and one end of the at least one acoustic vibration exciter is attached to the sound-emitting diaphragm within a dedicated line passing along the plane of the sound-emitting diaphragm, the dedicated line emanating from either top of the sound-emitting diaphragm and terminating at a point on the opposite top of the horizontal side of the diaphragm, the point being located at a horizontal distance of 2 / 3 from the top on the opposite side of the diaphragm.

[0013] The proposed invention enables the design and implementation of compact and efficient devices in fields where transverse wave acoustic radiation needs to be generated in a gaseous environment, not only for studying the properties of such radiation but also for its practical applications, such as loudspeaker forms with improved sound quality. Attached Figure Description

[0014] Figure 1 - An overall diagram of a device that emits transverse sound waves in a gaseous environment, indicating all the main components;

[0015] Figure 2 - Rear view of a device that emits transverse sound waves in a gaseous environment;

[0016] Figure 3 - A schematic diagram illustrating the conditions under which transverse sound waves appear in a gaseous environment;

[0017] Figure 4- An external view of the device that emits transverse sound waves;

[0018] Figure 5 - The location of the dedicated line within the plane of the sound-generating diaphragm, where it is recommended to place at least one or more acoustic vibration exciters. Detailed Implementation

[0019] The device for emitting transverse sound waves proposed in this invention ( Figure 1 The device includes: a support frame (1); a sound-generating diaphragm (2); an acoustic vibration drive (3), including some parts of a ferrite magnetic circuit and different types of coils: flat coil, square (rectangular) coil, wavy flat coil, cylindrical (circular) coil, star coil; and a rear support top cover (4) for the acoustic vibration drive.

[0020] For example, an acoustic vibration actuator (3) includes one (or more) acoustic vibration exciters comprising a housing in which the following components are disposed: a magnetic system, a cylindrical coil fixed to a frame, a system for holding the coil within a magnetic gap, and a flexible wire for supplying an electrical signal to the coil. The magnetic system is made of a cylindrical permanent magnet, a ferrite ring having the cylindrical magnet, and washers connecting them into a single structure. The cylindrical coil fixed to the frame is located above the cylindrical magnet and in the gap between the cylindrical magnet and the ferrite ring. The system for holding the coil within the magnetic gap consists of: two centering washers of different diameters, fixed at a distance from each other in the form of concentric corrugated disks; an inner hole fitted to the cylindrical coil and the frame; and an outer periphery fitted to the housing; and a flexible wire for supplying an electrical signal to the coil, sewn into one of the centering washers and welded at one end to a coil terminal and at the other end to an outer contact group. A cylindrical coil frame is attached to the sound-generating diaphragm (2).

[0021] The sound-emitting membrane (2) is made of a lightweight and rigid material. The sound-emitting membrane (2) is a sandwich structure comprising a honeycomb layer, a surface layer bonded to the honeycomb structure from both sides, and a stable impregnation composition based on a polyurethane primer and varnish covering the surface layer.

[0022] This sound-generating diaphragm (2) begins to transmit a traveling wave structure on the surface formed by an acoustic vibration actuator (3) attached to the surface of the sound-generating diaphragm. Waves traveling on the surface with a finite propagation speed in the diaphragm material and repeatedly reflected from the edges of the sound-generating diaphragm itself will form resonantly regulated frequency-dependent modulations, which are regionally located above the area of ​​the panel. These modulations have a distinct characteristic: they occur within an indivisible sound-generating diaphragm (2) in completely opposite balanced oscillations.

[0023] For ease of understanding, see [link to relevant documentation]. Figure 3 These opposing bending vibrations can be represented as a set of strictly out-of-phase, 180-degree incoherent point sound emitters (loudspeakers). This mode of operation of the proposed sound emitter is fundamental and necessary because the effective sound signal generation process stops in a mode beyond the resonant equilibrium formed by opposite modulations and the formation of transverse wave components is not required.

[0024] In addition, numerous practical experiments have enabled the establishment of a dedicated EB line that runs along the plane of the sound-generating diaphragm (see [link]). Figure 5 Within the dedicated line EB, an acoustic vibration exciter, or several acoustic vibration exciters, should be installed such that the point of the exciter's rotation axis lies on the dedicated line, or intersects with the front projection of the exciter circuit located near the dedicated line. Therefore, if we consider the diaphragms representing points A, B, C, and D (see...),... Figure 5 If the exciter's dedicated line passes from point B to point E, then E is a point on the DC side of the sound-emitting diaphragm, which divides the DC segment according to the following ratio: DE\EC = 1\2. One or more vibration exciters can be placed within the EB line. For a technical solution with one acoustic vibration exciter within this line, the X point needs to be determined according to the following ratio: EB\XB = 1.62. The dedicated line EB can naturally reflect symmetrically along any axis of symmetry of the sound-emitting diaphragm.

[0025] Assuming the excitation source is attached to the diaphragm region, the proposed technical solution's advantage of having a dedicated line within the diaphragm region ensures optimal distribution of resonant modulation within the diaphragm region. This, in turn, has a positive impact on the uniformity of the amplitude-frequency response and also ensures the naturalness of the sound (which is closely related to the reduction of the total amount of distortion and phase shift caused by the operation of the loudspeaker system) and ensures the maximum frequency range during the operation of such a system.

[0026] In the acoustic device of this invention, no special measures are required to maintain the conditions for the presence of transverse sound waves. The resonant mode of operation of this device assumes the continuous presence of suitable conditions for generating and maintaining transverse waves. Furthermore, these conditions exist as transverse wave radiation in the gas in a continuously available state at almost any frequency within the acoustic range, which, where necessary, includes a wider limitation in the low-frequency and high-frequency regions. Therefore, to implement radiation with a transverse component, it is sufficient to bring a single excitation source to a transmitter powered by a single-channel power amplifier and apply an appropriate signal (e.g., a sinusoidal signal of a specific frequency or broadband (“pink noise”), musical content, etc.).

[0027] exist Figure 4 The image shows an external view of the proposed acoustic device for transverse acoustic radiation in a gaseous environment.

[0028] At the same time, it is important to emphasize that it is virtually impossible to generate high-quality transverse acoustic waves at the Karavashkin device while transmitting signals of different frequencies and amplitudes to it. This is because all frequencies generated by a single piston emitter result in the acoustic Doppler effect. This undoubtedly makes it impossible to maintain phase coherence across the entire frequency range applied simultaneously.

[0029] In the configuration of this invention (where the sound-generating diaphragm is made of honeycomb material and the acoustic vibration exciter is located at a certain position on the diaphragm), when the frequency modulation is partitioned over a region of the panel, lower frequencies are not dominant relative to higher frequencies and the Doppler effect does not occur. Therefore, only this solution can continuously generate and sustain transverse sound waves in the gas across the entire frequency spectrum applied simultaneously, achieving the claimed technical results.

Claims

1. An acoustic device for emitting transverse sound waves in a gaseous environment, comprising a housing, a sound-emitting diaphragm, and an acoustic vibration actuator for the transverse sound waves, characterized in that, The housing is constructed in the form of a support frame, and the sound-emitting diaphragm is fixed to the support frame. The sound-generating membrane is made in the form of: a honeycomb layer, a surface layer bonded to the honeycomb layer from both sides, and a stable impregnation composition based on a polyurethane primer and varnish covering the surface layer; The acoustic vibration drive is made in the form of at least one acoustic vibration exciter, the at least one acoustic vibration exciter including a ferrite portion of a magnetic circuit; One of the ends of the at least one acoustic vibration exciter is attached to the sound-emitting membrane within a dedicated line passing through the plane of the sound-emitting membrane. The dedicated line originates from any vertex of the sound-emitting membrane and terminates at a point on the opposite side of the sound-emitting membrane where the horizontal vertex of the sound-emitting membrane is located. The point is located at a horizontal distance of 2 / 3 from the opposite vertex on the opposite side of the sound-emitting membrane. If the acoustic vibration drive is made in the form of an acoustic vibration exciter, the point of the rotation axis of the acoustic vibration exciter is located on the dedicated line, at a distance of 50 / 81 from any vertex of the dedicated line along the direction of the dedicated line.

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