JPH01123599A - Microphone - Google Patents

Abstract

PURPOSE:To prevent unnecessary resistance from being given at the time of vibration by providing a vibration part changing the relative position of a magnetic field and a superconductive substance with the aid of a sound wave and a detection part fetching the change of magnetic flux density at a prescribed part originated from the change of this relative position. CONSTITUTION:A microphone is constituted so as to fetch the change of the magnetic flux density generated by making the superconductive substance 3 to vibrate in the magnetic field of a permanent magnet 5 as one body with the vibration diaphragm 2 as electromotive force generated to the coil 6 of a pickup type. Then, this electromotive force is fetched through a conductor 7 conducting to the pickup coil 6 and a terminal 8 as a voltage signal. By using such superconductive substance 3, a special structure for fetching the electromotive force from a vibration system is not needed, the unnecessary resistance is hard to be given to the vibration diaphragm and the high sensitive microphone can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to microphones, and more particularly to improvements in microphones configured to generate electrical signals via a magnetic field by receiving sound waves.

[Conventional technology]

Conventionally, there is a moving coil type microphone configured as described above. In this moving coil type microphone, a solenoid-like coil is attached to the diaphragm, and a permanent magnet is installed near this coil. By arranging the diaphragm, the electromotive force generated within the coil is extracted when the coil is vibrated integrally with the diaphragm (references not listed).

[Problem that the invention seeks to solve]

However, in the moving coil type, as the coil vibrates integrally with the diaphragm as mentioned above, the conductor wire used to extract the electromotive force generated within the coil needs to have a flexible structure to allow vibration. However, since the coil protrudes from the diaphragm, air resistance becomes large, and vibration is easily suppressed due to the resistance when the conducting wire connected to the coil is bent, so there is room for improvement.

An object of the present invention is to construct a microphone that extracts electrical signals with a structure as simple as possible through rational modification, and that does not provide unnecessary resistance when the diaphragm vibrates. .

[Means for solving problems]

The present invention is characterized by a vibrating section that changes the relative position of the magnetic field and the superconducting material by receiving sound waves;
The present invention is comprised of detecting portions that detect changes in magnetic flux density at predetermined locations due to this relative positional change, and the mitigating actions and effects are as follows.

[For production]

If the above characteristics are configured as shown in FIG. 1, for example, the magnetic flux density of the magnetic field will change greatly due to the Meissner effect when the diaphragm (2) vibrates, so the detection unit will be located at the position where this change in magnetic flux density occurs. By arranging (B), it is possible to obtain an electromotive force signal without installing a coil etc. in the vibration system, and as shown in the figure, the vibration membrane (2
) is provided with an electromotive conductive material (3), and a permanent magnet (5) is provided on the vibrating membrane (2) as shown in Fig. 2, in which case a protrusion is formed on the vibrating membrane (2). In addition, it is possible to increase the voltage of the electromotive force by increasing the number of windings of the coil in the detection section (B).

〔Effect of the invention〕

Therefore, by modifying the system to use superconducting materials, there is no need for a special structure to extract electromotive force from the vibration system.
Furthermore, a highly sensitive microphone that does not easily impart unnecessary resistance to the diaphragm has been constructed.

In particular, in the present invention, by arranging the detection unit to detect changes in magnetic flux density caused by swirling currents generated inside the superconducting material by the Meissner effect when the diaphragm vibrates, electrical noise is not increased and sound waves are It also has the effect of obtaining twice the electrical signal. .

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

Figure 1 shows a cross section of a microphone, which consists of a circular diaphragm (2) whose outer periphery is attached to a ring-shaped frame (1), and a center of the diaphragm (2). A thin plate-shaped superconducting material (3) attached to the frame body (
The superconducting material (3) is connected to the support member (4) connected to the superconducting material (3).
A vibrating part (^) consisting of a permanent magnet (5) mounted close to the
6).

That is, the microphone uses magnetic flux density fluctuations caused by vibration of the vibrating membrane (2) and the superconducting material (3) in the magnetic field of the permanent magnet (5) as an electromotive force generated in the pickup-type coil (6). This electromotive force is taken out as a voltage signal via a conductive wire (7) and a terminal (8) that are electrically connected to the pickup coil (6).

[Another example]

In addition to the above-mentioned embodiment, the present invention also includes a permanent magnet (5) attached to the side of the vibrating membrane (2), and a superconducting material (3) attached to the fixed system, as shown in FIG. It is possible to obtain similar functions even if the configuration is substantially similar to that of the embodiment.

Further, the present invention may be implemented by using a thin diaphragm instead of the diaphragm, and by forming a thin film of superconducting material on the diaphragm or the like.

Further, in the present invention, an element capable of directly detecting changes in magnetic flux, such as a Hall element, may be used in the detection section, and furthermore, the detection section may be positioned at a position to detect changes in magnetic flux caused by swirling currents generated within the superconducting material. By arranging them, it is also possible to implement a configuration in which a signal having twice the frequency of the sound wave can be extracted while suppressing electrical noise.

Furthermore, the present invention may use currently developed superconducting materials and may also be used in a low-temperature environment.

Incidentally, although reference numerals are written in the claims section for convenient comparison with the drawings, the present invention is not limited to the structure shown in the accompanying drawings.

[Brief explanation of the drawing]

The drawings show an embodiment of the microphone according to the present invention, and FIG. 1 is a sectional view showing the structure of the microphone,
FIG. 2 is a sectional view showing the structure of a microphone according to another embodiment. (3)...Superconducting material, (A)...Vibrating part, (B)...Detecting part.

Claims (1)

[Claims] 1. By receiving sound waves, magnetic field and superconducting material (3
), a vibrating part (A) that changes its relative position with
A microphone comprising detection sections (B) each detecting a change in magnetic flux density at a predetermined portion due to this relative position change. 2. The vibrating part (A) includes a vibrating membrane (2) provided with a superconducting material (3), and a fixed permanent magnet (5) that forms a magnetic flux along the vibration direction of the vibrating membrane (2). It consists of
The microphone according to claim 1, wherein the detection section (B) is configured as a pickup-type coil (6). 3. The vibrating part (A) is composed of a vibrating membrane (2) provided with a permanent magnet (5) that forms a magnetic flux along the vibration direction, and a superconducting material (3) provided in a fixed system, and Detection unit(
The microphone according to claim 1, wherein B) is constituted by a pickup-type coil (6).