RU37291U1 - SPEAKER - Google Patents

Description

Speaker.

The proposed utility model relates to practical acoustics, namely, to the design of loudspeakers and relates to a loudspeaker based on a new principle of operation due to the use of two centrally bonded membranes stretching in antiphase.

The design of the proposed speaker provides high-quality reproduction of the lower frequencies of the audio range with small dimensions of the device.

In practical acoustics, high-quality reproduction of the lower frequencies of the sound range (20-100 Hz) is achieved by creating large sound pressure at these frequencies, which in turn is possible with significant oscillation amplitudes of the radiating surface and its large (comparable to wavelength) area. The simultaneous satisfaction of these two requirements for existing types of emitters faces significant difficulties associated with the need to increase the radiation area at sufficiently large oscillation amplitudes of the emitting surface. This leads to a significant increase in the dimensions of the low-frequency emitters.

WGM: HO4R 9/00 HO4R 7/00

sky, 2) electrostatic methods and 3) the method of creating longitudinal vibrations forming standing transverse waves in the membrane medium. The first two methods are based on the attraction and repulsion of the membrane from magnetic or electrostatic surfaces parallel to it. In this case, a contradiction insoluble in these types of emitters arises: to increase the amplitude of the oscillations, it is necessary to increase the distance between the oscillating radiating and attractive surfaces, but this leads to a weakening of the magnetic or electrostatic fields, which in turn again reduces the amplitude of the oscillations. Attenuation of sound pressure at low frequencies in this case has to be achieved by increasing the membrane area, which leads to an increase in the front dimensions of the emitter. The method of creating longitudinal vibrations in the membrane medium on existing materials does not allow creating transverse emitting waves sufficient to reproduce low frequencies of the oscillation amplitude.

The described types of flat emitters are implemented in the specific designs of many known loudspeakers (see, for example, Ru Ci 2193826, Ru Ci 2035842, Ru Ci 2043003, Ru Ci 2073959, Ru Ci 2110163, Ru C2 2189123, Ru Ci 2088045, etc.). For example, in the loudspeaker described in Ru JV2 patent 2193826 by making a passive emitter in the form of a synthetic film stretched over the loudspeaker body and paired with the diffuser of the electrodynamic head through a closed air gap, an increase in the radiation efficiency in the low-frequency region is achieved by increasing the acoustic coupling with environment and reduce distortion when reproducing sound signals of a non-periodic nature with a high rate of increase in amplitude due to the small mass passive radiation. The loudspeaker described in patent RU No. 2035842 contains a box with side, front and rear walls, an electro-acoustic transducer (one or several), interfaced with the mouth of the horn, the rectangular outlet of which and symmetrical phase-inverting holes are placed on the front wall of the box. Flush with

a panel with openings has been introduced to the upper, lower, and side walls, on which an electro-acoustic transducer (s) is installed, while the ratio of the volume of the cavity between the panel and the rear wall of the loudspeaker box to the sum of equal volumes of cavities between the walls of the speaker and the side walls of the loudspeaker box is in the range from 0 , 2 to 8.0. This design allows you to get a multi-resonant oscillatory system that provides sound emission when extending the frequency range to the low frequency region, including below the critical frequency of the horn. The loudspeaker described in patent Ru No. 2043003 contains permanent magnets, which are longitudinally magnetized plates facing each other with their planes and poles of the same name; sound magnets are made in the magnets, and the magnets form a through working gap with a high degree of field uniformity, into which the sound membrane is placed with electrically conductive strips deposited on it, which are elements of the voice coil.

Closest to the proposed utility model are loudspeakers in which the sound-emitting element is made in the form of a membrane. In addition to patent RU No. 2043003, the following can be cited as analogues. The loudspeaker according to patent RU No. 2110163 contains a magnetic circuit in the form of two steel plates with rows of flat, constant, mirror-mounted magnets placed on them, between which a flat dielectric membrane is installed on a fastening base in the form of two plates with central holes, on both sides of which are flat voice coils moreover, the filling of the magnetic system and the size of the magnets satisfy the relation: 0.05 Wg / Wm 0.75, where Wg is the distance between the rows of magnets on the plate, Wm is the width of the magnet, and the shape dimensions central hole plates studs bases correspond in shape and dimensions of the working surface of the membrane and the size of the field occupied by the magnets on the surface of each of the plates of the magnetic system.

Ru Patent No. 2018209 describes an electro-acoustic transducer that comprises a magnetic system, a voice coil and a membrane associated with it. The main differences relate to the implementation of the magnetic system, which consists of two axially magnetized permanent disk magnets aimed at meeting each other with the same poles, spacers located between them, two pole tips and a magnetic drive. The magnetic pad is made up of an odd number of layers, the middle of which is made of diamagnetic material, and the rest are made of two different types of soft anisotropic material.

Patent Ru JV 2088045 describes an electro-acoustic transducer comprising a cover with acoustic holes mounted on the free end of the housing, an electromechanical assembly, a sound-emitting element in the form of a membrane, coupled to an electromechanical assembly, a damper made of elastic material installed between the cover and the sound-emitting element, wherein the damper is in contact with the inner surface of the lid and has protrusions in contact with the sound emitting element by it along its entire outer surface.

For the prototype of the proposed loudspeaker, the loudspeaker described in the patent Ru. No. 2073959 (Ru Ci 2073959. Electrodynamic loudspeaker V. N. Karfidov; published 1997.02.20.) Was selected.

Like the proposed utility model, the prototype includes a sealed enclosure with evacuated internal volume, inside of which are located: a sound-emitting element containing a flat curved radiating membrane, a magnetic system, voice coils, corrugated elements for centering the coils associated with the body and sound-emitting element . The prototype uses a concave membrane loaded with atmospheric pressure; the coil is rigidly connected to the membrane and an elastic corrugated ring mounted on the frame of the housing.

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which would have small amplitude oscillations of the coil inside the magnetic field, would cause much larger amplitudes of oscillations of the membrane regions located in the center. The designs described in the analogs and prototype loudspeakers do not allow reducing the dimensions of the device, especially if it is necessary to reproduce low frequencies of the audio range, put forward high demands on the alignment of the membrane, and do not allow filling the gap between the magnets and the coil with a liquid magnetic circuit. The elimination of all these shortcomings is laid in the task of the proposed utility model. A new technical result achieved by using the loudspeaker proposed in this application is that due to the new principle of the loudspeaker’s operation due to the membrane mixing geometry, for the first time, it is possible for small amplitude oscillations of a flat coil inside the magnetic field to cause much larger oscillation amplitudes of the membrane regions centrally located. This, in turn, makes it possible to weaken the requirements for alignment of the membrane, to fill the gap between the magnets and the coil with a liquid magnetic circuit.

The task is achieved by the differences of the proposed loudspeaker, which consists in the fact that the emitting; th membrane is curved in the center and made with the possibility of stretching in relation to the radiation axis, as well as with the possibility of return movement due to the additional curved flat membrane curved with the neuron oppositely radiating to its membrane and stretching it in antiphase with respect to radiating; to this membrane, both membranes are fixed on corrugated elements made in the form of parallel to each other, the ends of the conductors on one membrane are connected by a flat flexible cable to the ends of the conductors located on the other membrane, so that a coil common to the membranes is formed, the magnetic system is made permanent magnets fixedly mounted on the base and

arranged in such a way that two different parts of the coil formed on different membranes make antiphase movements. In FIG. 1 shows a drawing of the proposed speaker. In FIG. 1 is indicated:

1-Base

2-membranes

3-Permanent Magnets

4-Center of the radiating membrane, the place of attachment of the two membranes

5-Corrugated Hangers

The new principle of operation of the loudspeaker is based on the stretching of a previously curved sound-emitting membrane (2) in the longitudinal direction with respect to the axis of sound emission. To ensure sinusoidal sound vibrations, two fastened ones are used in the loudspeaker, (4)

membranes stretched in antiphase. The alignment of the flat coils made at the ends of the membranes is drained by corrugated suspensions (5). Permanent magnets creating a magnetic field (3) are fixedly mounted on the base (1).

Due to the geometry of the membrane’s movement, small-amplitude oscillations of the flat coil inside the magnetic field cause much larger oscillation amplitudes of the membrane regions located in the center. This makes it possible to weaken the requirements for alignment of the membrane, fill the gap between the magnets and the coil with a liquid magnetic circuit, and significantly reduce the dimensions of the loudspeaker, especially when reproducing low frequencies of the sound range.

Claims (1)

A loudspeaker comprising a sealed enclosure with a evacuated internal volume, within which a sound-emitting element is placed, comprising a flat curved radiating membrane, a magnetic system, voice coils, corrugated elements for centering the coils associated with the body and the sound-emitting element, characterized in that the radiating membrane is curved center and made with the possibility of stretching in the longitudinal direction with respect to the radiation axis, as well as with the possibility of return movement due to additional a second planar membrane connected with it, curved opposite to the radiating membrane and stretching in antiphase with respect to the radiating membrane, both membranes are fixed on corrugated elements made in the form of suspensions mounted on a fixed base - frame, at the ends of the membranes are formed parallel parallel conductors, and the ends of the conductors on one membrane are connected by a flat flexible cable to the ends of the conductors located on another membrane, so that it forms a common coil for two membranes, the magnetic system is made in the form of permanent magnets fixedly mounted on the base and located in such a way that two different parts of the coil formed on different membranes make antiphase movements.