JPS61255199A - Low magnetic leakage speaker system - Google Patents

Abstract

PURPOSE:To constitute a system with a low cost by magnetically connecting two speakers magnetized with reversed polarity to each other. CONSTITUTION:Two speakers 13, 15 magnetized with reversed polarity to each other are approached to each other and a magnetic circuit of the two speakers 13, 15 is connected to a connecting member 17 constituted by a ferromagnetic material such as an iron plate. The connecting member 17 may be a conver shape as shown in the figure or a plate shape simply connecting bottom sections of pole piece plates. Thereby, the leakage magnetic flux generated from the first speaker 13 gives an influence to a remote place searching for the N pole mainly from the bottom section of the pole piece plate. According to the existence of the connecting member 17 of the ferromagnetic material, the magnetic flux is magnetically connected to the N pole of the pole piece plate of the second speaker 15 and does not leak outside.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a speaker system suitable for use in television sets and other video equipment equipped with cathode ray tubes, which are subject to large magnetic influences.

(Prior Art) An example of a magnetic low leakage speaker based on the prior art is shown in FIG. 2, using a pole piece plate 1. A voice coil 7 to which a signal current is applied is held in the center by a damper lO and a cone edge 9 and makes a piston motion in a magnetic gap formed by a ring-shaped magnet 2 and a top plate 3, and transmits the vibration to a cone 8. It becomes voice. The frame 6 is used to support the vibrating components and to attach the speaker to the cabinet. 4 is the pole piece plate 1. This is a ring-shaped cancellation magnet for bending leakage magnetic flux leaking from the magnetic circuit of the ring-shaped magnet 2 and the top plate 3, and is magnetized in the opposite direction to that of the ring-shaped magnet 2. Reference numeral 5 denotes a yoke cover made of a ferromagnetic material such as an iron plate for making the cancel magnet 4 into a closed circuit. According to such a configuration, magnetic leakage can be considerably reduced even in an external magnetic circuit employing a ferrite magnet or the like.

(Problem to be solved by the invention) However, in this configuration, the canceling magnet 4
However, the magnetic circuit is complicated and the cost is high.

An object of the present invention is to reduce magnetic leakage of an external magnetic speaker at low cost.

(Means for solving the problem) Two speakers magnetized with opposite polarities are brought close to each other, and the two magnetic circuits are connected by a connecting member made of a ferromagnetic material such as an iron plate.

(Function) The magnetic flux leaking from the magnetic circuit of the two speakers is caused by a ferromagnetic material with a relative magnetic permeability greater than 1 (greater than the magnetic permeability of air) because the two speakers are magnetized in opposite directions. Although they are mutually guided into the magnetic circuit of other speakers by the connecting member, they do not go outside, but act as if they are sucked into each other, and the leakage magnetic flux to the outside is drastically reduced.

(Embodiment) FIG. 1 shows a low magnetic leakage speaker system according to an embodiment of the present invention. Reference numeral 13 denotes a first speaker, and its configuration is exactly the same as the speaker shown in FIG. 2 except for the canceling magnet 4 and yoke cover 5. 14 is the magnet, and the magnetization direction is as shown in the figure. A second speaker 15 has the same structure as the first speaker 13, and its magnet 16 is magnetized in a direction opposite to that of the magnet 4 as shown in the figure. Reference numeral 17 denotes a connecting member made of a ferromagnetic (temporarily magnetic) material such as iron, which may be a cover-like member as shown in the figure, or a plate-like member that simply connects the bottoms of the pole piece plates.

In this embodiment configured as described above, the leakage magnetic flux generated from the first speaker 13 mainly seeks the N pole from the bottom of the pole piece plate and influences far away, but the ferromagnetic connecting member 17 Due to the presence of the second speaker 15
It is magnetically connected to the north pole of the pole piece plate and does not leak outside.

(Effects of the Invention) As described above, according to the present invention, by magnetically connecting two speakers, a low magnetic leakage speaker system can be constructed with a simple structure and at low cost.

[Brief explanation of drawings]

Fig. 2 is a block diagram of a speaker system according to an embodiment of the present invention, and Fig. 2 is a block diagram of a conventional example. 13, 15... Speaker, 14, 16... Magnet, 17... Connection member made of ferromagnetic material.

Claims (1)

[Claims] Each magnetic circuit of a first speaker having a magnet magnetized in one direction and a second speaker having a magnet magnetized in a direction opposite to the magnetization direction of the magnet of the first speaker is made of iron or the like. A low magnetic leakage speaker system characterized by being magnetically connected to each other by a connecting member made of a ferromagnetic material.