JPH11187485A - Loudspeaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a slender loudspeaker for use in various video devices that is not affected by an interference with sound emitted from a rear face. SOLUTION: A rising part of a voice coil 6 that is inserted to a magnetic circuit 5 which has a magnetic gap 4 to its upper and lower parts with the same magnetic flux directions is formed in this loudspeaker by forming a folded part in its inner side, while a frame 9 connects to an outer circumference of a yoke 2, and a diaphragm 8 connects respectively to the upper part and the lower part of the voice coil 6 nearly in the middle of the voice coil 6. This speaker is superior without deterioration in sound quality since it is free of interference from a rear side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a loudspeaker used for various video and audio equipment.

[0002]

2. Description of the Related Art A conventional speaker will be described with reference to a sectional view of FIG. In the figure, a plate 1 formed in a disk shape
1 is provided with a magnetic gap 13 in which a gap of a certain distance continues in a circle between the inner circumference of the yoke 12 and this magnetic gap 13.
A magnetic circuit 15 through which a magnetic flux 14 radially penetrates is constituted by a magnet 16.

[0003] Reference numeral 17 denotes a voice coil, which comprises at least a bobbin portion 18 formed in a cylindrical shape, and a coil portion 19 wound along the outer periphery of the bobbin portion 18 and inserted into the magnetic gap 13. Is coupled to the inner periphery of the diaphragm 22 coupled to the frame 21 via the edge 20 and the outer periphery is coupled to the inner periphery of a damper 23 coupled to the frame 21 so that the coil portion 19 It is supported to be inserted into the position.

In the loudspeaker constructed as described above, when a voice current flows through the coil portion 19 of the voice coil 17, the voice coil 17 vibrates up and down in accordance with the direction of the voice current. Vibrating plate 22
Are similarly vibrated and radiated to the outside as sound waves.

[0005]

However, in the above-mentioned loudspeaker, sound waves of opposite phases are radiated from the back surface of the diaphragm 22. Therefore, unless the sound waves from the back surface are cut off from the sound waves from the front surface, they interfere with each other. There is a problem that frequency characteristics are disturbed.

[0006]

In order to solve the above-mentioned problems, in a speaker according to the present invention, a coil is inserted into two upper and lower parallel magnetic gaps having the same magnetic flux direction, and the center of the upper and lower rising portions of the coil is bent inward. Since the voice coil and the diaphragm whose center is connected to the upper and lower portions of the voice coil and whose outer periphery is connected to the frame or the magnetic circuit are formed at two upper and lower portions, there is no influence of sound interference from the back. A speaker can be provided.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention according to claim 1 of the present invention relates to a magnetic circuit comprising a magnet connected between two yokes and two upper and lower parallel magnetic gaps having the same magnetic flux direction. A frame coupled to the magnetic circuit, a voice coil in which a coil is inserted into a magnetic gap of the magnetic circuit and the center of the upper and lower rising portions is bent inward, and a substantially central portion is coupled to an upper or lower portion of the voice coil and an outer periphery thereof. Are composed of diaphragms respectively arranged at the upper and lower positions coupled to the frame or the magnetic circuit, so that sound waves having the same phase are radiated from both diaphragms. Interference can be prevented.

According to a second aspect of the present invention, an elastic body is disposed on the inner peripheral portion of the voice coil according to the first aspect, and a sound wave is directly emitted from the voice coil without providing the diaphragm, thereby forming the diaphragm. It does not need to perform the same function as the speaker according to the first aspect.

An embodiment of a speaker according to the present invention will be described below with reference to FIGS.

(Embodiment 1) FIG. 1 is a cross-sectional view in a short diameter direction of a speaker according to an embodiment of the present invention, and FIG. 2 is a cross-sectional view in a long diameter direction. According to FIG. 1, reference numeral 1 denotes a magnet, which is coupled so as to be sandwiched between two yokes 2.
A magnetic gap 4 is provided so that the magnetic flux 3 is in the same direction above and below, and a magnetic circuit 5 is constituted as a whole. The voice coil 6 is bent inward at the center of the rising portion 7 in the vertical direction, so that the vibration of the voice coil 6 can be damped. Numeral 8 denotes a diaphragm having a substantially central portion connected to the upper and lower portions of the voice coil 6 and an outer periphery connected to the frame 9.

In the loudspeaker constructed as described above, when a voice current is applied to the voice coil 6 inserted in the upper and lower magnetic gaps 4, the upper and lower portions of the voice coil 6 vibrate in opposite directions. However, since the rising portion 7 of the voice coil 6 is bent inward, the upside-down vibration can be controlled, and in-phase sound waves are radiated from the front and rear diaphragms 8. Thus, it is possible to provide an excellent speaker that does not degrade the sound quality without interrupting the sound waves on the back.

The same effect can be obtained even if the outer periphery of the diaphragm 8 is connected to the magnetic circuit 5. (Embodiment 2) Another embodiment of the present invention will be described with reference to FIG. The same parts as those in the embodiment are denoted by the same reference numerals, and description thereof will be omitted. FIG. 3 is a sectional view of another embodiment of the present invention. According to the figure, the difference from the first embodiment is that there is no diaphragm and a sound wave is directly emitted from the voice coil 6, and an elastic body 10 is disposed inside the voice coil 6 to control the position of the voice coil 6. In addition, since the sound wave is not radiated from the inner peripheral side of the voice coil 6, an excellent speaker can be supplied at low cost without sound interference with the rear surface.

[0013]

As described above, the loudspeaker of the present invention has a magnetic circuit having two upper and lower parallel magnetic gaps in which the magnets are connected between two yokes and whose magnetic flux directions are the same. A voice coil in which a coil is inserted into the magnetic gap of the magnetic circuit and the center of the upper and lower rising portions is bent inward, and a substantially center is connected to the upper and lower portions of the voice coil and the outer periphery is the frame or the above. Vibration plates coupled to a magnetic circuit are arranged at two locations above and below, and sound waves having the same phase are radiated from both diaphragms, whereby interference of sound from the back surface can be prevented.

[Brief description of the drawings]

FIG. 1 is a sectional view of a loudspeaker according to an embodiment of the present invention in a minor diameter direction.

FIG. 2 is a sectional view in the same major axis direction.

FIG. 3 is a sectional view of a speaker according to another embodiment.

FIG. 4 is a sectional view of a conventional speaker.

[Explanation of symbols]

 Reference Signs List 1 magnet 2 yoke 3 magnetic flux 4 magnetic gap 5 magnetic circuit 6 voice coil 7 rising part 8 diaphragm 9 frame

Claims (2)

[Claims] 1. A magnetic circuit having a magnet coupled between at least two yokes and two upper and lower parallel magnetic gaps having the same magnetic flux direction, a frame coupled to the magnetic circuit, and the magnetic circuit. A voice coil in which a coil is inserted into the magnetic gap of the circuit and the center of the upper and lower rising portions is bent inward. A loudspeaker which is composed of diaphragms arranged at respective locations, and in which sound waves having the same phase are radiated from both diaphragms. 2. The loudspeaker according to claim 1, wherein an elastic body is arranged on an inner peripheral portion of the voice coil, and a sound wave is directly emitted from the voice coil without providing a diaphragm.