JPH11234795A - Electro-acoustic transducer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an equipment for supplying magnetic fluid without disassembling each part by forming a guiding part for supplying magnetic fluid at a member constituting the magnetic circuit of an electro-acoustic transducer filled with the magnetic fluid in a magnetic pole gap. SOLUTION: A guiding hole 11 formed at a yoke 1 and a pole 3 is formed so as to be put from the lower face of the yoke 1 through a position where a voice coil B is arranged. Therefore, even when magnetic fluid 6 is evaporated due to long-term use or heat of the voice coil B, the magnetic fluid 7 can be supplied by putting an injection needle through the guiding hole 11. Thus, the guiding hole 11 for supplying the magnetic fluid 6 is formed at a member constituting a magnetic circuit so that the magnetic fluid can be supplied through the guiding hole 11. Thus, the magnetic fluid 6 can be supplied without disassembling each part even when the magnetic fluid 6 is evaporated due to the long- term use or heat of the voice coil.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an electroacoustic transducer.

[0002]

2. Description of the Related Art Conventionally, an electroacoustic transducer such as a cone-shaped dynamic speaker basically has a disk-shaped yoke 1 and a ring-shaped fixed on the yoke 1, as shown in FIG. A magnet 2, a pole 3 integrally formed with the yoke 2 so as to rise upward at the center of the yoke, and a plate fixed to an upper surface of the magnet 2 and arranged such that an inner peripheral surface faces the pole 3. 4 and a magnetic pole gap 5 formed between the pole 3 and the plate 4, and a direction of a sound current to be supplied and arranged in the magnetic pole gap 5 of the magnetic circuit A and The voice coil B which moves up and down in the magnetic space 5 depending on the strength and the voice coil B formed in a cone shape
Of the voice current flowing through the voice coil B and the magnitude of the electromagnetic force generated by the voice current, i.e., The magnetic fluid 6, which has fluidity, for example, silicone (silicon resin) containing metal powder, is emphasized in the magnetic space 5 so that the amount of vertical movement of the voice coil B is substantially proportional to the amount of vertical movement. Was.

By appropriately adjusting the viscosity of the magnetic fluid 6, the amount of vertical movement of the voice coil B with respect to the amplitude of the voice current can be set in a substantially proportional relationship. Fluid 6 filled in
As a result, the heat from the voice coil B accompanying the supply of the audio current can be efficiently transmitted to the pole 3 and the plate 4, and the effect as a so-called heat sink has been obtained.

[0004]

The magnetic fluid filled in the magnetic voids of the magnetic circuit evaporates due to long-term use or heat generation of the voice coil, so that the above effects cannot be obtained. In this case, the magnetic fluid must be replenished. However, most of the electro-acoustic transducers are difficult to disassemble and replenish with magnetic fluid because each component is fixed with an adhesive, and when forcibly disassembled, the acoustic characteristics are degraded. Cannot replenish the magnetic fluid, and as a result, when the magnetic fluid evaporates due to long-term use or heat generation of the voice coil, there is a problem that it has to be replaced with a new electroacoustic transducer.

An object of the present invention is to provide an electroacoustic transducer that can replenish a magnetic fluid without disassembling each component.

[0006]

According to the present invention, there is provided an electroacoustic transducer for filling a magnetic fluid in a magnetic pole gap of a magnetic circuit. A guide portion for replenishing a fluid is formed.

Therefore, according to the present invention, the magnetic fluid can be replenished through the guide portion by forming the guide portion for replenishing the magnetic fluid on the members constituting the magnetic circuit.

[0008]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a side sectional view showing the structure of an electroacoustic transducer according to a first embodiment of the present invention, and FIG. 2 is a side sectional view showing the structure of an electroacoustic transducer according to a second embodiment of the present invention. FIG. 3 is a side sectional view showing a configuration of an electroacoustic transducer according to a third embodiment of the present invention, and FIG. 4 is a side cross sectional view showing a configuration of an electroacoustic transducer according to a fourth embodiment of the present invention. 5 is a side sectional view showing a configuration of an electro-acoustic transducer according to a fifth embodiment of the present invention, FIG. 6 is a side cross-sectional view showing a configuration of an electro-acoustic transducer according to a sixth embodiment of the present invention, and FIG. It is a figure showing composition of an electroacoustic transducer which is a 7th example of the present invention, (a) is a side sectional view, and (b) is a bottom view.

[First Embodiment] An electroacoustic transducer according to a first embodiment of the present invention will be described below with reference to FIG. still,
In FIG. 1, portions common to FIG. 8 are denoted by common reference numerals, and description thereof will be omitted.

Reference numeral 11 denotes a guide hole formed in the yoke 1 and the pole 3, and is formed to penetrate from the lower surface of the yoke 1 to a position where the voice coil B is arranged.

Therefore, according to the above configuration, even if the magnetic fluid 6 evaporates due to long-term use or heat generation of the voice coil B, the magnetic fluid 6 can be replenished through the injection needle through the guide hole 11.

Second Embodiment Hereinafter, an electroacoustic transducer according to a second embodiment of the present invention will be described with reference to FIG. still,
In FIG. 2, portions common to FIG. 8 are denoted by common reference numerals, and description thereof will be omitted.

Reference numeral 21 denotes a guide hole formed in the yoke 1, and is formed by penetrating the upper portion where the magnetic pole gap 5 is located.

Therefore, according to the above configuration, even if the magnetic fluid 6 evaporates due to long-term use or heat generation of the voice coil B, the magnetic fluid 6 can be replenished through the injection needle through the guide hole 21 and Replenishment of the magnetic fluid 6 to the outside and the inside of the voice coil B can be easily performed.

Third Embodiment An electroacoustic transducer according to a third embodiment of the present invention will be described below with reference to FIG. still,
In FIG. 3, portions common to FIG. 8 are denoted by common reference numerals, and description thereof is omitted.

Reference numeral 31 denotes a guide hole formed in the plate 4 and is formed to penetrate from the side of the plate 4 to a position where the voice coil B is arranged.

Therefore, according to the above configuration, even if the magnetic fluid 6 evaporates due to long-term use or heat generation of the voice coil B, the magnetic fluid 6 can be replenished through the injection needle through the guide hole 31 and The yoke 1 and the pole 3 common to the conventional electroacoustic transducer can be used.

[Fourth Embodiment] An electroacoustic transducer according to a fourth embodiment of the present invention will be described below with reference to FIG. still,
In FIG. 4, portions common to FIG. 8 are denoted by common reference numerals, and description thereof is omitted.

Reference numeral 41 denotes a guide hole formed in the yoke 1, and is formed by penetrating the upper portion where the magnetic pole gap 5 is located. Reference numeral 42 denotes a guide hole formed in the plate 4 and is formed to penetrate from a side portion of the plate 4 to a position where the voice coil B is arranged.

Therefore, according to the above configuration, even if the magnetic fluid 6 evaporates due to long-term use or heat generation of the voice coil B, the magnetic fluid 6 can be replenished through the injection needles through the guide holes 41 and 42. In addition, guide holes 41 and 42
Are located inside and outside the voice coil B, respectively, so that the magnetic fluid 6 can be replenished without moving the voice coil B.

[Fifth Embodiment] An electroacoustic transducer according to a fifth embodiment of the present invention will be described below with reference to FIG. still,
In FIG. 5, portions common to FIG. 8 are denoted by common reference numerals, and description thereof will be omitted.

Reference numeral 51 denotes a guide hole formed in the yoke 1 and the pole 3, and a first hole 51a formed vertically from the lower surface of the yoke 1 to a height at which the voice coil B is disposed, and a voice coil B disposed therein. The second hole 51b penetrates horizontally at the set height and a part of the second hole 51b communicates with the first hole 51a.

Therefore, according to the above configuration, even if the magnetic fluid 6 evaporates due to long-term use or heat generation of the voice coil B, the magnetic fluid 6 can be replenished through the injection needle through the guide hole 51, and Since the guide hole 51 has a single insertion port and a plurality of outlets, the time required for replenishment of the magnetic fluid 6 can be reduced.

[Sixth Embodiment] An electroacoustic transducer according to a sixth embodiment of the present invention will be described below with reference to FIG. still,
In FIG. 6, portions common to FIG. 8 are denoted by common reference numerals, and description thereof will be omitted.

Reference numerals 61 and 62 are guide holes formed in the yoke 1 and the pole 3, and are formed to penetrate from the lower surface of the yoke 1 to the position where the voice coil B is arranged.

Therefore, according to the above configuration, even if the magnetic fluid 6 evaporates due to long-term use or heat generation of the voice coil B, the magnetic fluid 6 can be replenished through the injection needles through the guide holes 61 and 62. At the same time, the magnetic fluid 6 is replenished by the plurality of linear guide holes 61 and 62,
The time required for replenishment of the magnetic fluid 6 can be reduced,
In addition, the injection needle can be easily inserted.

[Seventh Embodiment] An electroacoustic transducer according to a seventh embodiment of the present invention will be described below with reference to FIG. still,
In FIG. 7, portions common to FIG. 8 are denoted by common reference numerals, and description thereof will be omitted.

Reference numeral 71 denotes a guide hole formed in the yoke 1, and the guide hole 71 is formed at an upper portion thereof so as to penetrate a place where the magnetic pole gap 5 between the voice coil B and the plate 4 is located. Reference numeral 72 denotes a guide hole formed in the yoke 1, and a guide hole 72 formed between the voice coil B and the pole 3 is formed through the upper portion thereof. That is, as shown in FIG. 8, the guide hole 71 is on the circumference having substantially the same size as the inner diameter of the plate 4, and the guide hole 72 is on the circumference having the same size as the diameter of the pole 3.

Therefore, according to the above configuration, even if the magnetic fluid 6 evaporates due to long-term use or heat generation of the voice coil B, the magnetic fluid 6 can be replenished through the injection needles through the guide holes 71 and 72. At the same time, the magnetic fluid 6 can be easily replenished to the outside and inside of the voice coil B without moving the voice coil.

[0031]

As described above, according to the present invention, the magnetic fluid can be replenished through the guide portion by forming the guide portion for replenishing the magnetic fluid on the members constituting the magnetic circuit. Therefore, even if the magnetic fluid evaporates due to long-term use or heat generation of the voice coil, the magnetic fluid can be replenished without disassembling the components.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a configuration of an electroacoustic transducer according to a first embodiment of the present invention.

FIG. 2 is a side sectional view showing a configuration of an electroacoustic transducer according to a second embodiment of the present invention.

FIG. 3 is a side sectional view showing a configuration of an electroacoustic transducer according to a third embodiment of the present invention.

FIG. 4 is a side sectional view showing a configuration of an electroacoustic transducer according to a fourth embodiment of the present invention.

FIG. 5 is a side sectional view showing a configuration of an electroacoustic transducer according to a fifth embodiment of the present invention.

FIG. 6 is a side sectional view showing a configuration of an electroacoustic transducer according to a sixth embodiment of the present invention.

FIGS. 7A and 7B are diagrams showing a configuration of an electroacoustic transducer according to a seventh embodiment of the present invention, where FIG. 7A is a side sectional view and FIG. 7B is a bottom view.

FIG. 8 is a side sectional view showing the configuration of a conventional electroacoustic transducer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Yoke 2 Magnet 3 Pole 4 Plate 5 Magnetic pole gap 6 Magnetic fluid 11 Guide hole

Claims (1)

[Claims] 1. An electroacoustic transducer for filling a magnetic fluid into a magnetic pole gap of a magnetic circuit, wherein a member for forming the magnetic circuit is provided with a guide portion for replenishing the magnetic fluid. Electroacoustic transducer.