KR20110115866A - Linear vibrator having broadband - Google Patents

Abstract

The present invention relates to a linear vibrator having a wide bandwidth having a structure capable of outputting various vibrations at a wide bandwidth by allowing a small and large vibration force to be generated, the case providing an internal space, the case is disposed inside the case An elastic member, a magnet including a magnet and elastically supported by the elastic member and a stator fixed to the inside of the case to vibrate the vibrator, the magnet is an inner magnet disposed in the center of the outer magnet and the outer magnet The inner magnet and the outer magnet is provided with a linear vibrator having the opposite polarity in the vibration direction of the vibrator. Therefore, there is an advantage that can generate a variety of vibration and sound by using a wide frequency band.

Description

LINEAR VIBRATOR HAVING BROADBAND}

The present invention relates to a linear vibrator, and more particularly, to a linear vibrator having a wide bandwidth having a structure capable of outputting various vibrations at a wide bandwidth by allowing a small and large vibration force to be generated.

In general, the linear vibrator is used to generate vibration in a mobile communication terminal by using an electromagnetic force between the magnet and the coil. In particular, the demand for tactile touch is increasing and is being used in a variety of haptic devices. Recently, as the equipment using the vibrator is diversified and miniaturized, a linear vibrator capable of generating a small and large vibration amount is required.

1 shows a side cross-sectional view of a conventional linear vibrator. The coil 10, which generates an electromagnetic force by applying current to the lower center of the vibrator, is fixedly disposed, and the vibrator 20 is connected to the case 40 by a spring 30 having elasticity. The vibrator 20 has a weight 22 having a predetermined mass on an outer circumferential portion thereof and is coupled to the yoke 21, and the yoke 21 is spaced apart from the outer circumference of the coil 10 when the vibrator is viewed from above. It is made of a shape that surrounds. The magnet 23 having magnetic properties is disposed at the center of the yoke 21.

When a current is applied to the coil 10, the movement of the vibrator 20 is started by an electromagnetic force formed between the coil 10 and the magnet 23, and acts together with the elastic force of the spring 30 to vibrate the vibrator 20. ) Up and down vibration of the whole.

However, the conventional linear vibrator could feel the vibration only near the resonance frequency. Figure 2 shows the experimental value of the moving distance and the vibration amount according to the vibration frequency of the conventional vibrator.

The left graph of FIG. 2 shows the maximum moving distance of the vibrator in mm unit, and the right diagram shows the G-pack of the vibration amount as the root mean sqaure. The vibrator of the general linear vibrator is composed of one resonant frequency within the band of 100 ~ 300Hz, and in this limited range, a person can feel the vibration with the peak value of the moving distance and the vibration amount. In general, the amount of vibration that a human can feel in a haptic device is understood to be 0.2G or more. Looking at the measured graph, a vibration amount of a human sense can occur in a range of about 10 Hz in a 190 Hz band.

On the other hand, the frequency band that can be detected by human vibration or sound is understood to range from 20Hz to 20000Hz. However, a linear vibrator is generally installed to provide a touch when a button of a touch screen is pressed in a portable terminal using a haptic, and is mainly used because it can be miniaturized. In the case of such a linear vibrator there is a limit of the vibration force is to add a member such as the weight to increase the vibration force. However, since there is a limit of the vibration width and the vibration force of the linear vibrator, the problem of vibration force is solved mainly by using a peak value at the resonance frequency. Therefore, the vibration force is generated in a fairly limited region as shown in the experimental data shown in FIG. Thus, in the band of about 10Hz in the upper and lower range of the resonant frequency band, because the human can not sense the difference of the minute frequency, the hamtic device can only feel the vibration of the same feeling.

Therefore, the conventional linear vibrator has a problem that it is difficult to implement a variety of vibration feeling through the frequency variable because the range of vibration that a human can feel overall when touching the touch screen screen is within a range of about 10 hz, that is a fairly limited range.

In addition, in order to solve this problem, in order to widen the range of the actual use frequency band to generate various vibrations, that is, the use band generating vibration force of about 0.2G or more that a human can sense, Vibration should be generated over a range. As described above, due to the limitation of the size of the linear vibrator and the limitation of the vibration force, the vibration can be used only in a narrow region near the resonance frequency in most linear vibrators.

Accordingly, the present invention has been made in order to solve the above problems, it is possible to generate vibration in a wide range other than the resonant frequency, thereby having a structure that can have a high vibration force in a wide band so that various vibrations The aim is to provide a linear vibrator that can be sensed.

In addition, it is an object to provide a linear vibrator capable of outputting in a frequency band for generating a variety of vibrations as well as sound through a structure that can have a high vibration force.

In addition, an object of the present invention is to provide a mobile device having a linear vibrator capable of maximizing user satisfaction by outputting various vibrations and sounds simultaneously in a mobile device using a haptic.

The linear vibrator according to the present invention for solving the above problems includes a case providing an internal space, an elastic member disposed inside the case, a magnet and being elastically supported by the elastic member and the inside of the case. And a stator configured to vibrate the vibrator, wherein the magnet is formed of an outer magnet and an inner magnet disposed at the center of the outer magnet, and the inner magnet and the outer magnet have opposite polarities in the vibration direction of the vibrator. Provide a linear vibrator. Therefore, there is an advantage that can provide sufficient vibration force in a wide frequency band.

In addition, the linear vibrator according to the present invention provides a linear vibrator including an upper plate disposed between the magnet and the elastic member, and a lower plate coupled to the lower end of the magnet. Thus, there is an advantage that a linear vibrator is provided which can be further increased in the vibratory force of the vibrator.

In addition, the linear vibrator according to the present invention provides a linear vibrator made of at least one of the upper plate and the lower plate of a magnetic material. Accordingly, there is an advantage that the leakage of the flux flux is minimized and the vibration efficiency by the electromagnetic force is maximized.

In addition, the linear vibrator according to the present invention provides a linear vibrator, wherein the lower plate is an outer plate coupled to the lower end of the outer magnet and an inner plate coupled to the lower end of the inner magnet. Thus, a structure that can minimize the magnetic flux leakage of the magnet is provided.

In addition, the linear vibrator according to the present invention provides a linear vibrator having a volume ratio of the outer magnet and the inner magnet in the range of 0.8 to 1. Therefore, there is an advantage that the vibration efficiency is further increased.

In addition, the linear vibrator according to the present invention provides a linear vibrator in which the resonant frequency of the linear vibrator is set lower than the use frequency that can be detected as a vibration or sound source. Therefore, since the region higher than the resonant frequency range can be utilized as the actual use frequency, there is an advantage that a linear vibrator capable of generating vibration in a wide band is provided.

In addition, the linear vibrator according to the present invention provides a linear vibrator for oscillating the oscillation frequency that can be sensed to the upper and lower sides of the resonant frequency in the range of 30 to 150Hz, respectively. Thus, a linear vibrator with a wide bandwidth is provided.

In addition, the linear vibrator according to the present invention provides a linear vibrator having a frequency band up to the maximum use frequency that can be detected as a vibration or sound source based on the resonance frequency is 1.2 times or more than the frequency band up to the minimum use frequency. Thus, a linear vibrator is provided in which vibration can occur up to a frequency range farther than the resonant frequency.

Since the bandwidth of the vibration is significantly wider than the prior art by the linear vibrator according to the present invention configured as described above, the frequency range detected by the user using it is widened to experience a variety of sense of vibration There is this.

In addition, there is provided a linear vibrator capable of generating a sufficient vibration force in a wide range there is an advantage that can provide a variety of vibration sense in a limited size.

In addition, there is an advantage in the mobile device using the haptic can provide vibration as well as sound at the same time.

1 is a side cross-sectional view of a linear vibrator according to the prior art.
2 is a graph showing the relationship between the frequency of the linear vibrator according to the prior art, the moving distance and the vibration force of the vibrator.
3 is a model of a two degree of freedom system of a linear vibrator.
4 is a side cross-sectional view of a linear vibrator according to an embodiment of the present invention.
5 is a graph showing the relationship between the frequency of the linear vibrator and the moving distance and vibration force of the vibrator according to an embodiment of the present invention.

Hereinafter, a linear vibrator according to a preferred embodiment of the present invention with reference to the accompanying drawings will be described in detail.

3 is a simplified illustration of a two degree of freedom system of a linear vibrator. In the system, m1 represents the mass of a portable device involving a mobile phone or touch liquid crystal, and m2 represents the mass of an oscillator. Indicated by c is the respective damping coefficient and k is the elastic modulus of the spring. Vibrators are usually housed inside and coupled to the equipment, from the top of the two degree of freedom system to equipment and shock absorbers, such as vibrators and cell phones.

If a two degree of freedom system of such a configuration is represented by a formula, it can be expressed as follows.

x and y represent the displacement of the vibrator and the displacement of the cellular phone equipment, and matrix A represents the overall matrix of the system. In addition, F value means the vibration force by electromagnetic force.

Where the value of F is related to weight, distance traveled and angular frequency. In the simplest terms,

Becomes Here, m is mass, d is moving distance, and ω (2πf) is angular frequency. As in the formula, force is proportional to mass and moving distance, and is proportional to square of angular frequency.

Accordingly, the present invention proposes a concept that allows the vibrator to vibrate in a wide region up and down based on the resonance frequency. That is, the linear vibrator according to the prior art generates a vibration that can only be detected in a limited region of the resonant frequency, so that in the frequency range of use frequency that can actually detect the vibration to widen the band of the vibration that can be detected At low frequencies, the resonant frequency is set.

Since the resonant frequency is related to the mass and stiffness of the whole system, it can be set by changing the mass and stiffness. The present invention preferably determines the resonant frequency band within the 80 ~ 180HZ band. When the resonant frequency band is determined as described above, the use frequency range is used in the region higher than the resonant frequency, and thus vibration can be generated in a wide range. However, when the vibration occurs in a wide area outside the resonant frequency as described in the prior art is proposed a structural problem to improve the vibration force to generate a vibration force that can be detected, which will be described later.

On the other hand, it should be noted that the concept of setting the resonant frequency lower than the actual useable frequency is not understood to be a vibration that can be detected in the region below the resonant frequency. That is, when compared with FIG. 2 showing the prior art, in the prior art, the peak value is shown at the resonance frequency, and the vibration force is sharply reduced in the upper and lower regions of the resonance frequency. For this reason, as described above, vibrations that can be detected only in a very limited region above and below the resonance frequency are generated. However, when the resonant frequency is placed in the low range of the use frequency, the graph of the experimental value showing the relationship between the frequency and the vibration force draws a gentle curve as will be described later. The vibration can be generated. Therefore, the resonance frequency is preferably set at a low frequency in the real use frequency range that can be detected.

According to the above concept, a concept in which the frequency band up to the maximum use frequency that can be detected as a vibration or sound source based on the resonance frequency is wider than the frequency band up to the minimum use frequency is proposed. From this point of view, referring to FIG. 2 showing experimental data of a linear vibrator of the prior art, it can be easily understood that the difference in the range of generating vibration that can be detected based on a resonance frequency indicating a peak value is not large.

On the other hand, in the linear vibrator according to the present invention, it should be noted that the high band is wider than the low band based on the resonance frequency. Preferably, the ratio of the high band bandwidth to the low band is preferably at least 1.2.

For example, if the resonant frequency is 140 Hz and the minimum frequency is 30 Hz at the use frequency, the maximum frequency is set to 272 Hz or more, and the bandwidth of the use frequency of the linear vibrator is set to 30 to 272 Hz or more, so that most of the range of vibration that can be detected Various vibrations can be generated in the.

Accordingly, a linear vibrator is provided which oscillates a vibration frequency that can be sensed in the range of 30 Hz to 150 Hz at frequencies above and below the resonance frequency, respectively. Of course, the frequency band may be set in a wider range to provide sound.

On the other hand, in order to generate a vibration that can be detected by a person in the band higher than the resonant frequency, the force to move the vibrator, that is, the F value should be set large. Accordingly, the linear vibrator according to the present invention preferably proposes a concept of replacing the weight of the prior art with a magnet, and improving the vibration force of the vibrator through the arrangement.

4 shows a side sectional view of a vibrator according to the invention. Similar to the vibrator of the prior art, the spring 300 is disposed on the upper inner surface of the case 400 forming the outer surface of the vibrator, and the vibrator 200 is disposed below and elastically supported. The vibrator 200 is formed in a substantially disk shape, the magnet is disposed below. At the bottom of the case 400, the coil 100 is fixedly spaced apart from the vibrator 200 by a predetermined interval. Looking at the shape of the vibrator 200 in more detail, preferably, the inner magnet 232 is disposed on the central side of the vibrator 200 and the outer magnet 231 is disposed adjacent to the outer circumferential surface.

Therefore, in the space between the outer magnet 231 and the inner magnet 232, the coil 100 disposed below the case 400 is disposed between the magnets 231 and 232 in the horizontal direction. Since the direction of the magnetic flux between the inner circumferential surface and the outer circumferential surface of the coil 100 is formed in a mutually opposite direction, as described above, the outer magnet 231 and the inner magnet 232 are disposed on the inner circumferential side and the outer circumferential side of the coil, respectively. More efficient.

The coil 100 is spaced apart from the outer circumferential surface of the inner magnet 232 and the inner circumferential surface of the outer magnet 231. When a current is applied to the coil 100, the coils 100 are interposed between the magnets 231 and 232. The vibrator moves up and down by the electromagnetic force and vibrates by the elastic force of the spring 300. The magnets 231 and 232 and the spring 300 may be formed in the shape of being reversed by being disposed under the case 400, and the magnet is not supported by the spring 300 through the magnetic body 210 and is directly supported by the spring 300. Of course, it can be supported (300).

In addition, in place of the yoke of the prior art, the upper plate 211 is interposed between the spring 300 and the magnets (231, 232). In addition, it is more preferable that the lower plates 212 and 213 are also arranged at the lower end of the magnet. Accordingly, the plates 211, 212, and 213 are disposed at both upper and lower ends of the magnets 231 and 232 and have a predetermined mass, thereby replacing the weight of the prior art. In addition, the bottom plate 212 is a bottom plate 213 disposed on the lower end of the lower plate 212 and the inner magnet 232 in the donut shape when the magnet is made of the outer and the inner, respectively, in a donut shape. ).

On the other hand, more preferably the outer magnet 231 and the inner magnet 232 is disposed to have a magnetic flux in the opposite direction. Because the magnetic flux is formed in the opposite direction inside and outside the coil, respectively, because the polarity of the outer magnet 231 and the inner magnet 232 must be formed in the opposite direction to maximize the electromagnetic force. Therefore, in Fig. 4, the magnetic fluxes arranged in the opposite polarities are indicated by arrows.

The magnetic flux of the inner magnet 232 is below the vibrator, the outer magnet 231 is formed upward, so that the vibration force can be maximized by applying the current of the coil 100 in an appropriate direction. However, the direction of the magnetic flux may of course be set in the opposite direction according to the direction of the current and the rotation direction of the coil.

On the other hand, the plate 211, 212, 213 is used to replace the weight and yoke of the prior art to increase the flux flux, more preferably made of a magnetic material. Therefore, although the material of the plates is preferably made of silicon steel sheet or pure iron, it is of course possible to selectively use a material that can minimize magnetic flux leakage. As the magnetic body 210 is used as described above, the leakage of the magnetic flux can be minimized to increase the magnetic flux, so that the efficiency of the electromagnetic force generated between the coil and the coil can be improved, thereby further improving the vibration force of the vibrator.

Looking at the arrangement of the upper plate 211 and the lower plate (212, 213) as described above in more detail based on Figure 4, the back yoke portion that serves as the frame of the conventional vibrator is replaced by a plate-shaped upper plate 211 do. Therefore, the upper plate 211 made of the magnetic material is elastically supported by the spring 300 at the upper side, and supports the inner magnet 232 and the outer magnet 231 at the lower side.

In addition, as described above, the vibrator preferably includes a magnetic material at the lower ends of the magnets 231 and 232. Accordingly, the lower plates 212 and 213 are provided at the lower ends of the outer magnet 231 and the inner magnet 232, respectively, and the lower inner plate 212 is disposed at the lower ends of the inner magnet 232 according to the shape of the magnet. ) Is made in the shape of a disc in the cross-section, the lower outer plate 213 disposed at the lower end of the outer magnet 231 is made of a donut shape.

On the other hand, the lower plate (212, 213) as described above, even if the magnet is not separated into the outside and the inside is arranged as in the prior art can be disposed at the end of the upper and lower side, respectively, of course to improve the magnetic flux efficiency to be.

As described above, according to the concept that the magnetic bodies are disposed above and below the magnet, the magnetic flux does not leak to the outside at both ends of the magnet, and the vertical vibration can be generated faithfully by the electromagnetic force between the coils. As such, the vibration efficiency due to the applied current is further improved.

Further, preferably, the volume ratio of the outer magnet 231 and the inner magnet 232 is approximately one. Therefore, it is more preferable that the said volume ratio is determined in the range of 0.8-1. In this case, since the volume ratio is almost the same, the ratio of the magnetic flux passing through is equalized, and thus, the magnetic flux efficiency and the vibration force can be further contributed.

The vibrator according to the concept of the present invention configured as described above has a large difference in vibration force since the conventional vibrator generates a force of about 2 to 3 g · f, while generating a force of about 20 g · f. .

Figure 5 shows the experimental data on the moving distance and the vibration amount of the vibrator when the majority of the use frequency is higher than the resonant frequency in accordance with the concept of the present invention and the vibration force is increased according to the structure of the linear vibrator according to the present invention. In the above experiment, m1 was 0.1 kg, m2 was 0.0008 kg, k1 was 11.3 N / m, k2 was 1070 N / m, c1 was 3.31 Ns / m, c2 was 0.6 Ns / m, and F was set to 0.35 N.

5 shows the moving distance of the vibrator according to the frequency, while the resonance frequency is lowered to about 100 Hz while the distribution of the moving distance shows the moving distance of 0.4 mm or more over the range of about 200 Hz near the resonance frequency. do.

5 shows the vibration amount of the vibrator according to the frequency, the peak value of the vibration amount is slightly lower than that of FIG. . This means that an effective vibration occurred in the range of 100 Hz or more, and the user can sense other vibrations of a wide frequency band through the sense of a finger touch.

Meanwhile, a mobile device in which the linear vibrator according to the concept of the present invention is disposed will be described.

Along with vision and hearing, interest in mobile devices is increasing in recent years with the most important sense function, and a device using such a touch is called a haptic device. Such haptic devices are used in various fields such as smartphones and portable PCs in virtual reality, wearable computers, and robotics. These are called haptic interfaces.

As described in relation to the problems of the prior art, there is a problem in that a mobile device using a linear vibrator cannot utilize various vibrations due to limitations in size and vibration force, and to solve such a problem, a linear vibrator according to the concept of the present invention. Has been presented as above.

A mobile device generally includes a display for outputting an image, a touch pad for receiving an execution command through a touch, a vibration unit for providing a vibration output, an audio output unit for outputting sound, and a controller for outputting an image, sound, and vibration control signal. Is done. The vibrator is used to arrange the linear vibrator of the present invention.

In the configuration of the linear vibrator according to the present invention, the vibration force can be increased, and accordingly, the bandwidth for generating the vibration is widened, so that various vibrations can be output, and the bandwidth can be set higher. . When the bandwidth rises from several kHz to several tens of kHz, it can output not only vibration but also sound.

Accordingly, according to another concept of the present invention, a mobile device having a linear vibrator capable of simultaneously outputting sound and vibration is provided. Therefore, depending on the setting, the vibration and the sound may be respectively output from the same linear vibrator or may be output together. In addition, when increasing the size and output of the linear vibrator can be used to replace the sound output unit. As such, when the vibrator replaces the speaker functioning as the sound output, it should be noted that the mobile device has the advantage of being structurally simple and miniaturized.

As described above, in the case of a mobile device having a linear vibrator capable of simultaneously outputting sound and vibration, it is preferable that the controller can set the vibration mode and the sound mode, respectively. Therefore, when the vibration mode is set to less than approximately 300Hz frequency is set to the use frequency can be detected vibration output, when the acoustic mode is set to approximately 300Hz to 15,000Hz frequency is used to detect sound You can do it. In addition, when the diaphragm or the vibration plate is provided inside the linear vibrator or inside the mobile device, the effect of sound or vibration may be further increased, and the sound and vibration may occur simultaneously. On the other hand, the linear vibrator may be provided as a single, but of course two or more may be arranged as necessary.

By the linear vibrator according to the concept of the present invention configured as described above, because the bandwidth of the vibration is significantly wider than the prior art, the frequency range detected by the user using it is widened to experience a variety of sense of vibration There is an advantage. In addition, by providing a structure that can provide a strong electromagnetic force to complement the setting of the practical range of the vibration frequency out of the resonant frequency range, the effect of a wide-band vibrator can be further increased.

In the above, the present invention has been described in detail based on the embodiment and the accompanying drawings. However, the scope of the present invention is not limited by the above embodiments and drawings, and the scope of the present invention will be limited only by the contents described in the claims below.

100 ... coil 200 ... vibrator
211 ... top plate 212 ... bottom inner plate
213.Lower outer plate 231 ... Outer magnet
232 Inner magnet 300 Spring
400 ... case

Claims (8)

A case providing an interior space;
An elastic member disposed inside the case;
A vibrator including a magnet and elastically supported by the elastic member; And
And a stator fixed inside the case to vibrate the vibrator.
The magnet is composed of an outer magnet and an inner magnet disposed in the center of the outer magnet,
The inner magnet and the outer magnet is a linear vibrator having an opposite polarity in the vibration direction of the vibrator.
The method of claim 1,
An upper plate disposed between the magnet and the elastic member; And,
And a lower plate coupled to the lower end of the magnet.
The method of claim 2,
At least one of the upper plate and the lower plate is a linear vibrator made of a magnetic material.
The method of claim 2,
And the lower plate is an outer plate coupled to a lower end of the outer magnet and an inner plate coupled to a lower end of the inner magnet.
The method of claim 1,
The volume ratio of the outer magnet and the inner magnet is in the range of 0.8 to 1 linear vibrator.
The method according to any one of claims 1 to 5,
Resonant frequency of the linear vibrator is a linear vibrator is set lower than the operating frequency that can be detected as a vibration or sound source.
The method according to any one of claims 1 to 5,
A linear vibrator for oscillating the oscillation frequency that can be detected in the upper and lower sides of the resonant frequency in the range of 30 to 150 Hz, respectively.
The method according to any one of claims 1 to 5,
A linear vibrator with a frequency band up to the maximum frequency that can be detected as a vibration or sound source based on the resonance frequency is 1.2 times or more than the frequency band up to the minimum frequency.

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