RU164962U1 - ELECTRODYNAMIC SPEAKER - Google Patents

Abstract

1. An electrodynamic loudspeaker comprising a body of non-magnetic material with a magnetic system housed in it, including two ring permanent magnets of different diameters and four pole pieces, forming two coaxial ring air gaps, in which a voice coil connected with the possibility of free axial movement is connected with a centering washer and a diffuser through an annular frame of non-magnetic material with a sectioned winding placed on it, characterized in that the winding of its sound kovoy coil consists of a number, the number of at least four axially arranged and electrically interconnected sections, each of which is connected to a separate signal source supplying the supply voltage only in those sections which are located in air zazorah.2. The loudspeaker according to claim 1, characterized in that the conductor of its voice coil is a metal tape rolled on a frame, the thickness of which in the radial direction is much smaller than its width, equal to the size of a separate section in the axial direction, and not exceeding half the axial distance between the pole pieces, that is, half the height of the permanent magnets in the axial direction.

Description

Electrodynamic loudspeaker

The utility model relates to radio engineering and can be used in acoustic systems of the low-frequency part of the sound range with a high level of signal amplitude and other devices emitting low- and infra-low-frequency waves.

A device is known that contains a magnetic system of two having different diameters located in the same plane of the ring permanent magnets with axial magnetization with ring pole pieces arranged at both poles, forming two coaxial ring air gaps, both magnets being oppositely directed by their poles. In the air gaps there is a voice coil with the possibility of its free movement in the axial direction, the winding of which consists of two spaced apart sections located on a common annular frame, each of which is located in a separate air gap, the height of which in the axial direction is less than the axial height a separate section of the voice coil (see article CN 102905214 A DRIVER FOR TRANSDUCER WITH TWO MAGNETS, TWO MAGNETIC GAPS AND TWO COILS, Zhang Fan, dated January 31, 2013, p. 20), prototype.

The disadvantages of the prototype are: low efficiency of converting electrical energy into mechanical energy, due to the fact that part of the conductor of the voice coil is outside the air gaps, that is, where the magnetic field decreases, and with increasing amplitude of movement of the voice coil, the magnitude of this part increases; the low maximum stroke of the voice coil, due to the fact that during its movement, as its sections approach the opposite air gaps, the braking effect begins to act on the coil, since the magnetic fluxes in the air gaps are opposite in direction, N-S and S-N.

The technical result consists in increasing and maintaining at a constant level the efficiency of energy conversion in the voice coil, regardless of its maximum working stroke, as well as increasing the maximum working stroke of the voice coil by changing its design and optimizing the power supply to the windings of the voice coil. The technical result is achieved by the fact that the electrodynamic loudspeaker has a body of non-magnetic material with a magnetic system located in it, including two coaxial annular air gaps, with an annular sectioned voice coil located in them with the possibility of its free reciprocating movement, the frame of which is connected with centering washer and diffuser. The peculiarity is that the winding of the voice coil is divided into several, at least four, placed on a single frame of non-magnetic material sections that are not electrically connected and formed by roll winding of a thin metal tape coated on all sides with an electrically insulating material, with the tape width equal to the axial height of an individual section should not exceed half the axial height of the permanent magnets, and the gap between adjacent sections should be as small as possible.

The essence of the utility model is illustrated by graphic materials, which depict: in FIG. 1 is an axial sectional view of the design of an electrodynamic loudspeaker; in FIG. 2 is a photograph of a voice coil layout.

The electrodynamic loudspeaker (Fig. 1) contains a housing made of non-magnetic material 1, in which a magnetic system is placed, which includes two ring permanent magnets 2 and 3 of different diameters, at the poles of each of which ring pole tips made of soft magnetic steel 4, 5, 6 are placed , 7. Magnets 2 and 3 are located in the same plane, have axial magnetization and are counter-directed by their magnetic poles. Pole lugs 4 and 6 have outer diameters smaller than the diameters of the holes of the pole lugs 5 and 7 and are respectively placed in these holes, forming two annular air gaps 8 and 9 of a minimum width in the radial direction, sufficient for free reciprocating movement of the ring sound coil, which is connected by its frame 10 to the centering washer 11 and the diffuser 12. On the ring frame of non-magnetic material 10 there is a winding formed by several identical axially arranged laid and electrically unconnected annular sections 13, the conductor of which is a thin metal tape rolled on a surface of a carcass 10 and coated over the entire surface with an electrically insulating material. The width of the tape, as well as the axial height of the individual section 13 should not exceed half the distance between the pole pieces 4 and 6, 5 and 7, respectively, as well as half the height in the axial direction of the ring magnets 2 and 3. The number of sections 13 should be at least four, and the axial distance between adjacent sections 13 should be minimal, sufficient to ensure electrical insulation between them. Each section 13 is connected to a separate source of electrical signal through conclusions 14 (Fig. 2), organized by bending the conductor ribbon at an angle of 90 degrees to its longitudinal axis. Pulses of an electric signal are fed only to those groups of sections of the voice coil that, as a result of its axial movement, are at least partially in the air gaps 8 and 9. The parameters of the pulses are set by an external monitoring device (not shown in Fig.) Depending on the parameters of the initial sound signal and the signal generated by the displacement sensor of the voice coil 15 installed near one of the air gaps 8, 9. In FIG. 1 shows one of the options for its placement. The device of the sensor 15 can be based on the principle of conversion into an electrical signal reflected from the surface of the voice coil of an optical beam or an ultrasonic wave.

Changing the design of the voice coil by dividing its conductor into electrically isolated sections, and supplying the supply voltage only to those located in the air gaps of the magnetic system, can improve the energy conversion efficiency and also increase the maximum working stroke of the voice coil, without causing a decrease in efficiency energy conversion device.

Claims (2)

1. An electrodynamic loudspeaker comprising a body of non-magnetic material with a magnetic system housed in it, including two ring permanent magnets of different diameters and four pole pieces, forming two coaxial ring air gaps, in which a voice coil connected with the possibility of free axial movement is connected with a centering washer and a diffuser through an annular frame of non-magnetic material with a sectioned winding placed on it, characterized in that the winding of its sound kovoy coil consists of a number, the number of at least four axially arranged and electrically interconnected sections, each of which is connected to a separate signal source supplying the supply voltage only in those sections which are located in the air gaps. 2. The loudspeaker according to claim 1, characterized in that the conductor of its voice coil is a metal tape rolled on a frame, the thickness of which in the radial direction is much smaller than its width, equal to the size of a separate section in the axial direction, and not exceeding half the axial distance between the pole tips, that is, half the height of the permanent magnets in the axial direction.

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