JPH0833096A - Electro/mechanical vibration transducer device - Google Patents

Abstract

PURPOSE:To provide an electro/mechanical vibration transducer device which is capable of imparting the vibration of the heavy low-pitched sound area of the frequency according to the taste of a body feeling person by changing the natural vibration of a device body in the adjusting mechanism provided between a yoke and a diaphragm. CONSTITUTION:The diaphragm 20 and the yoke 22 of this electro/mechanical vibration transducer device 18 is mounted so that they may freely vibrate in a relatively vertical direction. The diaphragm 20 is formed into a disk shape by material such as aluminum, etc. A nut 36 is placed at the intermediate location of an adjusting range and a music signal is impressed on a coil 38. The diaphragm 20 of the transducer device 18 vibrates most by the resonance frequency that the natural frequency of a device body and the frequency of the music signal are matched. When the nut 36 is tightened and a damper 34 is compressed, the natural frequency of the device body becomes high. When the nut 36 is loosen, the natural frequency becomes low. Therefore, the natural frequency of the device can be freely adjusted.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electro-mechanical vibration converter for a sensible vibration generator that generates a sensible vibration by an electric signal in a low tone range.

[0002]

2. Description of the Related Art When listening to music or the like, when the frequency of sound becomes low, about 150 Hz or less, the sound is not confirmed by the viewer by vibrating the eardrum, but air vibration as sound pressure. The specific gravity felt by the body increases. The extremely low part of the audible frequency, that is, the deep bass, is the sound pressure that is felt by the skin and the body as air vibration. You will feel it.

Therefore, also in the sound reproducing apparatus, in order to ideally feel the deep bass, as shown in FIG. 8, the sensation experienced by the body is synchronized with the electric signal for driving the speaker etc. An electro-mechanical vibration converter 118 for generating vibration is known. This electro-mechanical vibration converter 118 includes a yoke 12 having a magnetic pole 124.
2, the coil 138 wound around the coil frame 130 is arranged in the magnetic gap 128, and the coil 138 vibrates due to the magnetic interference action generated between the magnetic force generated in the coil 138 and the magnetic force of the magnetic pole 124 in accordance with the electric signal from the sound source. Therefore, the yoke 122 is supported via the first damper 156 and the second damper 158 in the form of a flat plate so that the yoke 122 and the coil 138 are relatively displaced.

Such an electro-mechanical vibration converter 118
Has the highest vibration efficiency near the natural frequency of the main body of the device with respect to the applied signal. Further, a signal obtained by electrically cutting a middle-high frequency signal that cannot be oscillated by the electro-mechanical vibration converter 118 is applied by a low-pass filter or a band-pass filter circuit.

[0005]

However, as shown in FIG. 4, the frequency near the natural frequency of the main body of the apparatus, which is capable of efficiently reacting to the applied signal, that is, the resonance frequency range, is reproduced in a constant range. The area was limited, and the vibration sensitivity was low except near the resonance frequency. As a result, different individuals have different tastes in the deep bass range, and some people feel uncomfortable. Also, in order to match the taste, a low-pass filter and a band-pass filter circuit were used to selectively apply an arbitrary frequency signal.However, only the region matching the resonance frequency was reacted, and the frequency matching the preference was applied. It was not possible to answer the request to experience deep bass.

The present invention has been made in order to solve the above-mentioned problems, and provides an electro-mechanical vibration converter capable of giving vibration in the deep bass range of a frequency according to the taste of the experienced person. To do.

[0007]

In order to achieve this object, the electromechanical vibration converter of the present invention forms a magnetic air gap by a yoke having magnetic poles, and arranges a coil in the air gap. By applying an electric signal to the coil, the diaphragm that transmits the vibration to the outside of the device is vibrated by the magnetic interference effect generated between the magnetic force generated in the coil and the magnetic force of the magnetic pole, and the natural frequency of the device main body is changed. An adjusting mechanism that can be used is provided between the yoke and the diaphragm.

Further, the adjusting mechanism is composed of an elastic body arranged between the yoke and a holding shaft for holding the diaphragm, and a pressing means for adjustingably pressing the elastic body against the yoke. However, the natural frequency may be made variable by adjusting the pressing force for pressing the elastic body.

Further, it is preferable that the elastic body has a non-linear relationship between the change in the pressing force when the pressing force of the elastic body is changed and the repulsive force of the elastic body.

The elastic body may be made of rubber.

Further, the pressing means may be composed of a screw and a nut.

[0012]

In the electro-mechanical vibration converter of the present invention having the above-mentioned structure, the desired frequency can be obtained by changing the natural frequency of the apparatus body by the adjusting mechanism provided between the yoke and the diaphragm. be able to.

Further, it is possible to change the natural frequency by adjusting the pressing force for pressing the elastic body arranged between the yoke and the holding shaft holding the diaphragm against the yoke by the pressing means.

Furthermore, since the relationship between the change in the pressing force when the elastic body is pressed and the repulsive force of the elastic body are non-linear, the natural frequency can be easily changed.

Since the elastic body is made of rubber,
The natural frequency can be easily changed.

Further, when the nut is tightened and the rubber is compressed, the natural frequency increases, and when the nut is loosened, the natural frequency decreases.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment embodying the electro-mechanical vibration device of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of an electro-mechanical vibration converter. The electro-mechanical vibration converter 18 includes a yoke 2
2, a magnetic pole 24 attached to the yoke 22, a plate 26 located above the magnetic pole 24, a hole 26a provided in the plate 26, and a column portion 2 of the yoke 22.
2a, a coil frame 30 arranged in a magnetic gap 28, a coil 38 wound around an outer peripheral portion 30a of the coil frame 30, and a vibration for transmitting the vibration to the outside of the apparatus main body by a magnetic interference action. It is composed of a plate 20, a holding shaft 32 for holding the diaphragm 20, and an adjusting mechanism 42 capable of varying the natural frequency of the apparatus body.

The vibrating plate 20 is formed in a disk shape from a material such as aluminum, and has a hole at the center for fitting and connecting the holding shaft 32.

The coil frame 30 is formed of a material such as paper in a cylindrical shape. The coil frame 30 is fixed to the lower surface of the diaphragm 20 so that the center of the circle of the coil frame 30 and the center of the circle of the diaphragm 20 coincide with each other. A coil is wound around the outer periphery of the coil frame 30.

The bottom of the yoke 22 is made of a material such as iron,
The support 22a is formed in a substantially disc shape, and is formed in a cylindrical shape. At the center of the yoke 22, the holding shaft 3
A through hole 22b is provided so that 2 can penetrate.

The plate 26 is made of a material such as iron and has a disk shape, and has the same size as the diameter of the bottom portion of the yoke 22. A hole is formed in the central portion of the plate 26 so that the pillar portion 22a of the yoke 22 and the coil frame 30 can be accommodated.

The magnetic pole 24 is formed in an annular shape from a material such as a permanent magnet, and is arranged between the bottom portion of the yoke 22 and the plate 26.

The holding shaft 32 is formed of a material such as iron into a cylindrical shape, and has a female screw 32a as a part of the adjusting mechanism at the lower end thereof. A damper pressing plate 40 for pressing a damper 34, which will be described later, is provided near the upper portion of the holding shaft 32. Further, the holding shaft 32 penetrates the through hole 22b, and the upper end thereof reaches the diaphragm 20.

The adjusting mechanism 42 includes a damper 34 made of the annular elastic body arranged near the lower end and the upper end of the holding shaft 32, and a female screw 32a provided at the lower end of the holding shaft 32. It is composed of a nut 36.

The damper 34 is made of a material such as rubber and is sandwiched between the upper end of the yoke 22 and the damper retainer plate 40, and the damper 34 near the lower end.
Are sandwiched between the lower end of the yoke 22 and the nut 36.

In the electro-mechanical vibration converter having the above-mentioned structure, the diaphragm 20 and the yoke 22 are formed so as to be relatively movable in the vertical direction.

Next, the relationship between the adjusting mechanism 42 and the resonance frequency will be described in detail.

The resonance frequency f is represented by f = 2π√ (k / m). Here, π represents the circular constant, m represents the mass of the vibration system, and k represents the spring constant. Since both the pi and the mass of the vibration system are fixed, the resonance frequency f can be changed by changing the spring constant k.
The spring constant k is represented by the ratio of the repulsive force P to the amplitude S of vibration (amount of tightening of the elastic body) S at the position where the elastic body is installed. That is, k = P ÷ S.

Therefore, the relationship between the repulsive force of the damper 34 and the tightening amount of the nut 36 in this embodiment is shown in FIG. The slope of the graph in FIG. 5 represents the spring constant k. Further, when the conical coil spring is used as the elastic body, the relationship between the repulsive force and the tightening amount of the nut 36 is illustrated in FIG. Since the graphs of FIGS. 5 and 7 are non-linear in which the inclination changes, the spring constant k can be changed. On the other hand, when the elastic body having a shape like a cylindrical coil spring is used, the relationship between the repulsive force and the tightening amount of the nut 36 is shown in FIG. Since the graph of FIG. 6 has a constant linear inclination, the spring constant k cannot be changed.

Next, the operation of the electro-mechanical vibration converter of this embodiment will be described.

A music signal is applied to the coil 38 by setting the nut 36 at an intermediate position in the adjustment range. Normal music signal is 2
Although the frequency is in the range of about 0 Hz to 20 KHz, the vibration plate 20 of the electro-mechanical vibration converter 18 has a resonance frequency matching the natural frequency of the device body and the frequency of the music signal, as shown in FIG. For example, it vibrates most at around 80 Hz.

Next, when the nut 36 is tightened and the damper 34 is compressed, the natural frequency of the apparatus main body increases. this is,
This is because as the tightening amount increases, the inclination of the graph becomes steeper as shown in FIG. 5, and the spring constant k also increases. For example, by tightening the nut 36, k becomes 2
When it is doubled, f becomes 1.41 times, and when the natural frequency before the adjustment is 80 Hz, the natural frequency after the adjustment becomes 113HZ. Similarly, when the nut 36 is loosened, the natural frequency becomes low. Therefore, with respect to these arbitrarily adjusted natural frequencies, it is possible to vibrate well with respect to an electric signal having a frequency close to this.

As is clear from the above description, the electromechanical vibration converter of the present embodiment is an adjusting mechanism provided between the yoke and the diaphragm, and changes the natural frequency of the main body of the apparatus. A desired frequency can be obtained.

The present invention is not limited to the embodiments described in detail above, and various modifications can be made without departing from the spirit of the invention. In this embodiment, as shown in FIG. 1, the nut 36 is attached so as to sandwich the yoke 22 and the annular damper 34 between the upper and lower ends of the yoke 22, but for example, the second nut shown in FIG. As in the embodiment, one cylindrical damper 52 is arranged at the center of the yoke 22, and the cylindrical damper 52 is compressed by the cylindrical load rings 50 arranged so as to sandwich the cylindrical damper 52 at the two upper and lower positions. You may do it. Note that the same reference numerals as those in FIG. 1 are the same as those in FIG.

Further, as in the third embodiment shown in FIG.
The air gap 28 and the coil 38 may be located near the outer periphery of the device, and the yoke 22 may be formed in a pot shape. The same reference numerals as those in FIG. 1 denote the same parts in FIG.

Further, a conical coil spring may be used as the elastic member.

[0038]

As is apparent from the above description, the electro-mechanical vibration converter according to the present invention uses the adjusting mechanism provided between the yoke and the diaphragm to change the natural frequency of the device body. Can obtain a desired frequency.

Further, the natural frequency can be changed by adjusting the pressing force for pressing the elastic body arranged between the yoke and the holding shaft holding the diaphragm against the yoke by the pressing means.

Further, since the relationship between the change in the pressing force when the elastic body is pressed and the repulsive force of the elastic body is non-linear, the natural frequency can be easily changed.

Since the elastic body is made of rubber,
The natural frequency can be easily changed.

Further, when the nut is tightened and the rubber is compressed, the natural frequency is increased, and when the nut is loosened, the natural frequency is lowered, so that the natural frequency can be easily adjusted. To be

[Brief description of drawings]

FIG. 1 is a sectional view of an electro-mechanical vibration converter according to a first embodiment of the present invention.

FIG. 2 is a sectional view of an electro-mechanical vibration converter according to a second embodiment of the present invention.

FIG. 3 is a sectional view of an electro-mechanical vibration converter according to a third embodiment of the present invention.

FIG. 4 is a graph of a relationship between a frequency and a vibration level indicating a resonance frequency region.

FIG. 5 is a relationship diagram of the repulsive force of the damper with respect to the tightening amount of the adjustment nut.

FIG. 6 is a relationship diagram of a repulsive force of a cylindrical coil spring with respect to a tightening amount of an adjustment nut.

FIG. 7 is a relationship diagram of the repulsive force of the conical coil spring with respect to the tightening amount of the adjustment nut.

FIG. 8 is a sectional view of a conventional electro-mechanical vibration converter.

[Explanation of symbols]

 18 Electro-Mechanical Vibration Converter 20 Vibrating Plate 22 Yoke 22b Through Hole 24 Magnetic Pole 28 Gap 30 Coil Frame 32 Holding Shaft 32 Female Screw Part 34 Damper 36 Nut 38 Coil 40 Damper Pressing Plate 42 Adjusting Mechanism

Claims (5)

[Claims] 1. A magnetic air gap is formed by a yoke having magnetic poles, a coil is arranged in the air gap, and an electric signal is applied to the coil, so that the magnetic force generated in the coil and the magnetic force of the magnetic pole. In an electro-mechanical vibration conversion device that vibrates a diaphragm that transmits vibration to the outside of the device by a magnetic interference action that occurs between the yoke and the diaphragm, an adjustment mechanism that can change the natural frequency of the device body is used. An electro-mechanical vibration converter characterized by being provided between. 2. The adjusting mechanism is configured by an elastic body arranged between the yoke and a holding shaft holding the diaphragm, and a pressing unit that adjustably presses the elastic body against the yoke. The electric-mechanical vibration converter according to claim 1, wherein the natural frequency can be varied by adjusting the pressing force for pressing the elastic body. 3. The elastic body according to claim 2, wherein the relationship between the change of the pressing force when the pressing force of the elastic body is changed and the repulsive force of the elastic body is non-linear. The described electro-mechanical vibration converter. 4. The electro-mechanical vibration converter according to claim 2, wherein the elastic body is made of rubber. 5. The electro-mechanical vibration converter according to claim 2, wherein the pressing means is composed of a screw and a nut.