Vibration device

Abstract

This oscillation device includes: an oscillator that imparts oscillation; a displacement detection unit that detects displacement of the oscillator or a housing; and a control unit that causes the oscillator to oscillate on the basis of a drive signal which was inputted and detection information from the displacement detection unit.

Description

[Technical field]

[0001] The technology of this disclosure relates to vibration devices. [Background technology]

[0002] JP 2021-186710 A discloses a technology for mechanically suppressing vibration by arranging multiple coil springs on both sides of a movable element to obtain vibration suppression effects and durability. Summary of the Invention [Problem to be solved by the invention]

[0003] Incidentally, it is preferable to prevent the vibrator from coming into contact with the housing.

[0004] In consideration of the above, the technique of the present disclosure has an object to provide a vibration device that can prevent a vibrator from coming into contact with a housing. [Means for solving the problem]

[0005] One aspect of the present disclosure is a vibration device that includes a vibrator that provides vibration, a displacement detection unit that detects displacement of the vibrator or a housing, and a control unit that vibrates the vibrator based on an input drive signal and detection information from the displacement detection unit. Effect of the Invention

[0006] As described above, according to the vibration device of the technique of the present disclosure, it is possible to prevent the vibrator from coming into contact with the housing. [Brief description of the drawings]

[0007] [Figure 1] 1 is a schematic diagram of a vibration device according to an embodiment of the technique of the present disclosure. [Diagram 2] 2 is a block diagram showing a configuration of a control unit of a vibration device according to a first embodiment of the technique of the present disclosure. FIG. [Diagram 3]FIG. 11 is a diagram for explaining a method of adjusting a control signal. [Figure 4] FIG. 13 is a diagram for explaining a method of adjusting the level of a drive signal so as to suppress it when the compression ratio is "2:1" and the threshold value TH is "10." [Diagram 5] FIG. 13 is a diagram for explaining a method of adjusting the level of a drive signal so as to suppress it when the compression ratio is "3:1" and the threshold value TH is "15." [Figure 6] 5 is a flowchart showing a vibration control processing routine performed by a control unit of the vibration device according to the first embodiment of the technique of the present disclosure. [Figure 7A] 13 is a diagram for explaining a method of adjusting the level of a drive signal so as to suppress it according to a combination of the movement direction and acceleration of a vibrator. FIG. [Figure 7B] 13 is a diagram for explaining a method of adjusting the level of a drive signal so as to suppress it according to a combination of the movement direction and acceleration of a vibrator. FIG. [Figure 7C] 13 is a diagram for explaining a method of adjusting the level of a drive signal so as to suppress it according to a combination of the movement direction and acceleration of a vibrator. FIG. [Figure 7D] 13 is a diagram for explaining a method of adjusting the level of a drive signal so as to suppress it according to a combination of the movement direction and acceleration of a vibrator. FIG. [Figure 8] 13 is a block diagram showing a configuration of a control unit of a vibration device according to a fourth embodiment of the technique of the present disclosure. FIG. [Figure 9] 13 is a flowchart showing a vibration control processing routine performed by a control unit of a vibration device according to a fourth embodiment of the technique of the present disclosure. [Figure 10] 13 is a block diagram showing a configuration of a control unit of a vibration device according to a fifth embodiment of the technique of the present disclosure. FIG. [Figure 11] 13 is a flowchart showing a vibration control processing routine performed by a control unit of a vibration device according to a fifth embodiment of the technique disclosed herein. [Figure 12] 13 is a block diagram showing a configuration of a control unit of a vibration device according to a sixth embodiment of the technique of the present disclosure. FIG. [Figure 13]13 is a block diagram showing a configuration of a control unit of a vibration device according to a seventh embodiment of the technique of the present disclosure. FIG. [Figure 14] 11 is a graph showing changes in a control signal, a magnetic force, and a position of a transducer. [Figure 15A] FIG. 1 is a perspective view showing a configuration of a vibration device according to a conventional technique. [Figure 15B] FIG. 1 is a schematic diagram showing a stationary state of a vibration device according to the prior art. [Figure 16A] FIG. 1 is a schematic diagram showing a driving state of a vibration device according to a conventional technique. [Figure 16B] FIG. 1 is a schematic diagram showing a driving state of a vibration device according to a conventional technique. [Figure 16C] FIG. 1 is a schematic diagram showing a driving state of a vibration device according to a conventional technique. [Figure 17] 13 is a schematic diagram of a vibration device according to an eighth embodiment of the technology of the present disclosure. FIG. [Figure 18A] 13 is a cross-sectional view showing a configuration of an actuator of a vibration device according to an eighth embodiment of the technique of the present disclosure. FIG. [Figure 18B] 13 is a schematic diagram showing a configuration of an actuator of a vibration device according to an eighth embodiment of the technique of the present disclosure. FIG. [Figure 19A] 13 is a schematic diagram showing the connection relationship between an actuator and a control unit of a vibration device according to an eighth embodiment of the technique of the present disclosure. FIG. [Figure 19B] FIG. 2 is a diagram showing the configuration of a magnetic circuit having one coil. [Figure 20A] 13 is a graph showing the magnitude, x component, and z component of magnetic flux versus displacement at the center of a side surface of a housing of a magnetic circuit having a pair of coils. [Figure 20B] 13 is a graph showing the magnitude, x component, and z component of magnetic flux versus displacement at the center of the top surface of a housing of a magnetic circuit having a pair of coils. [Figure 21A] 13 is a graph showing the magnitude, x-component, and z-component of magnetic flux versus displacement at the center of a side surface of a housing of a magnetic circuit having one coil. [Figure 21B]13 is a graph showing the magnitude, x component, and z component of magnetic flux versus displacement at the center of the top surface of a housing of a magnetic circuit having one coil. [Figure 21C] 13 is a graph showing the magnitude, x-component, and z-component of magnetic flux versus displacement at the center of the bottom surface of a housing of a magnetic circuit having one coil. [Figure 21D] 13 is a graph showing the magnitude, x component, and z component of magnetic flux versus displacement at a position 4 mm from the center of the side of the housing of a magnetic circuit having one coil toward the coil. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Hereinafter, embodiments of the technology of the present disclosure will be described in detail with reference to the drawings.

[0009] <Overview of the embodiment of the technology disclosed herein> Voice coil actuators as shown in Fig. 15A are used to transmit vibrations to the hand, body, etc. and to reproduce artificial sensations and tactile sensations. Voice coil actuators are built into game controllers, massagers, etc., and are often used in environments that are not constant but constantly changing, such as being held in the hand or in contact with the body.

[0010] As shown in FIG. 15B, the voice coil actuator has a magnet supported by a suspension in a housing. FIG. 15B is a cross-sectional view showing an example of the internal structure of a voice coil actuator in a stationary state. When the voice coil actuator is driven, depending on the usage state, the internal magnet may physically come into contact with the inner wall of the housing, generating abnormal noise. This is particularly noticeable in devices that are held in the hand and are not used in a constant state (e.g., game controllers, massagers, etc.). In addition, this is likely to occur when the voice coil actuator is driven with a drive signal close to the resonant frequency of the voice coil actuator or a drive signal with the maximum allowable frequency, which is used when it is desired to transmit large vibrations.

[0011] The conditions of use that cause abnormal noise will be specifically described below.

[0012] First, as shown in Fig. 16A, there are cases where a large load is applied to the voice coil actuator when the device in which the voice coil actuator is mounted is tightly gripped or pressed down, etc. In such cases, the device body and the housing of the voice coil actuator itself are physically fixed, the amount of movement of the magnet relative to the housing of the voice coil actuator becomes maximum, and the magnet is likely to come into contact with the inner wall of the housing.

[0013] Furthermore, as shown in FIG. 16B, when the load on the voice coil actuator is extremely light (the voice coil actuator is free), the housing vibrates too much, causing the magnet to move significantly relative to the housing, causing contact between the magnet and housing and generating abnormal noise.

[0014] On the other hand, as shown in FIG. 16C, when the load on the voice coil actuator is moderate, the vibration of the device body is offset by the vibration of the magnet in the voice coil actuator, reducing the amount of movement of the magnet relative to the housing and making contact with the housing less likely to occur.

[0015] It is possible to prevent the magnet from coming into contact with the housing by uniformly reducing the input drive signal according to the usage conditions that cause the above-mentioned abnormal noise, i.e., narrowing the dynamic range. However, this would result in a reduction in the overall vibration and a weaker tactile sensation.

[0016] Therefore, in the embodiment of the technology disclosed herein, a magnetic detection sensor is provided on the outside of the housing of the actuator, and the movement direction and acceleration of the vibrator are identified based on the change in the position of the internal vibrator (magnet) that changes depending on the input, and the level of the control signal is controlled based on the movement direction and acceleration, thereby suppressing the movement of the vibrator just before it physically hits the housing, or comparing it with the input drive signal and outputting a control signal according to the difference to the actuator 10, thereby controlling the vibration of the vibrator 12. Since the movement of the vibrator is directly captured and used to drive and control the vibrator, it is possible to respond to various fluctuations in physical loads. In addition, since the movement of the vibrator is captured, control is possible even when an excessive drive signal is input.

[0017] Since the direction of motion can be determined based on the input drive signal and the sensor signal input from the magnetic detection sensor, the magnetic detection sensor can be installed anywhere on the outside of the housing. This allows application to existing actuators of various shapes. In other words, there is no need to modify existing actuators.

[0018] [First embodiment] <Configuration of the vibration device according to the first embodiment of the technique of the present disclosure> FIG. 1 shows a schematic diagram of a vibration device 100 according to an embodiment of the technique of this disclosure.

[0019] 1, the vibration device 100 includes an actuator 10, a magnetic detection sensor 20 provided on the surface of a housing 10A, and a control unit 30. The actuator 10 includes a housing 10A, a vibrator 12 provided within the housing 10A, and a suspension 14 that supports the vibrator 12. The actuator 10 is, for example, a voice coil type actuator.

[0020] The magnetic detection sensor 20 detects magnetic force, which is the magnitude of magnetism from the vibrator 12, which changes in response to the input of a drive signal. As the vibrator 12 moves within the housing 10A in response to the input of a drive signal, the difference in magnetic force is detected based on the positional relationship between the vibrator 12 and the magnetic detection sensor 20. As the magnetic detection sensor 20, for example, a linear type Hall element can be used.

[0021] As shown in FIG. 2, the control unit 30 includes a drive signal input unit 32, a sensor signal input unit 34, an AD conversion unit 36, a determination unit 38, a signal adjustment unit 40, and a drive circuit 42.

[0022] The drive signal input unit 32 receives the input of a drive signal from an external source (for example, an audio player, a game controller, a massager, etc.). Note that, although the case where the drive signal is received from an external source has been described as an example, the present invention is not limited to this. For example, a signal pattern or a sound source signal stored in advance, or a signal pattern or a sound source signal generated by a program may be received as the drive signal.

[0023] The sensor signal input unit 34 receives an input of a sensor signal corresponding to the magnetic force detected by the magnetic detection sensor 20.

[0024] The AD conversion unit 36 ​​performs AD conversion of the sensor signal received by the sensor signal input unit 34, and outputs a digital signal.

[0025] The determination unit 38 determines, based on the output of the AD conversion unit 36, whether or not the magnetic force detected by the magnetic detection sensor 20 is equal to or greater than a threshold value.

[0026] When it is determined that the magnetic force detected by the magnetic detection sensor 20 is equal to or greater than the threshold value, the signal adjustment unit 40 adjusts the level of the drive signal based on the magnetic force detected by the magnetic detection sensor 20 so as to suppress it.

[0027] The drive circuit 42 outputs a control signal to the actuator 10 for vibrating the vibrator 12 in response to the drive signal.

[0028] Next, the adjustment method performed by the signal adjustment unit 40 will be described.

[0029] There are various possible methods of use and fixing the vibration device 100. The relationship between the level of the drive signal and the detected magnetic force in various methods of use and fixing is shown in FIG.

[0030] As shown in Figure 3, when the main body is firmly fixed or when it is left completely free and floating (see the dashed line in Figure 3), magnetic force is detected along a line starting from the drive signal level "0."

[0031] Also, when the transducer is held loosely to a certain extent and the amplitude of the transducer is relatively minimum (see the two-dot chain line in FIG. 3), the magnetic force is detected along the line starting from the drive signal level "10."

[0032] Furthermore, when it is assumed that the main body, such as a game controller, will be moved (see the dotted and dashed lines in Figure 3), it is conceivable that the main body may be moved in a direction greater than when it is firmly fixed, or less than when it is held somewhat loosely, and effective control is required even in such cases.

[0033] For this reason, the drive signal level is adjusted in the dotted regions shown in Figure 3. Moreover, in the dotted regions, the adjustment is made larger the higher one goes.

[0034] In this embodiment, a compression method is used as an example of a method for adjusting the drive signal. In this compression method, the magnetic force detected by the magnetic detection sensor 20 is used as the position of the vibrator 12 (permanent magnet), and when the value exceeds a set threshold value TH, the output level of the drive signal is adjusted at a set compression ratio.

[0035] For example, as shown in Fig. 4, when the threshold value TH is "10", the output level of the drive signal is adjusted to be suppressed at a predetermined compression ratio when the magnetic force is "10" or more. Here, when the magnetic force is "20" or more, it is assumed that the magnetic force reaches a plateau (contacts the housing 10A) (see the dotted area in Fig. 4). Also, the output level is permitted up to "30".

[0036] If the compression ratio is set to "2:1", even if the magnetic force is at its maximum value of "20", it can be handled by outputting the upper limit of the drive signal output level, "30". Note that the triangular area (gray area in Fig. 4) connecting the threshold value TH "10", the magnetic force "20", and the drive signal output level "30" cannot be used. Also, if you try to match the magnetic force to "20" at an output level of "30" without suppressing the drive signal output level, it is necessary to suppress the overall output level of the drive signal so that the maximum magnetic force is "20" (see the thin dashed line (OUT1:1MAX30) in Fig. 4). In that case, the vibration transmitted will be smaller overall.

[0037] The compression ratio is used as the ratio at which the amount of the drive signal that exceeds the input level corresponding to the threshold value TH is compressed when the threshold value TH is exceeded. For example, "2:1", "3:1", "4:1", etc. can be used.

[0038] For example, if the amount exceeding the input level "10" corresponding to the magnetic force threshold value "10" is set to "10", the output level for each compression ratio will be as follows:

[0039] Compression Ratio Output 2:1 → 15(=10+5) 3:1 → 13.3(=10+3.3) 4:1 → 12.5(=10+2.5) 5:1 → 12(=10+2)

[0040] Also, as shown in FIG. 5, when the threshold value TH is "15", the output level of the drive signal is adjusted to be suppressed at a predetermined compression ratio when the magnetic force is "15" or more. If the compression ratio is "3:1", even if the maximum magnetic force is "20", it can be handled by outputting "30", which is the upper limit of the output level of the drive signal. Note that the triangular area (gray area in FIG. 5) connecting the threshold value TH "15", the magnetic force "20", and the output level "30" cannot be used. However, it is smaller than the triangular area when the threshold value TH is "10" in FIG. 4 above. Also, if you try to match the magnetic force to "20" at the output level "30" without suppressing the output level of the drive signal, you need to suppress the output level of the drive signal overall so that the maximum magnetic force is "20" (see the thin dashed line (OUT1:1MAX30) in FIG. 5). In that case, the vibration transmitted will be smaller overall.

[0041] As can be seen from Figures 4 and 5 above, by setting the threshold value TH as high as possible and reducing the compression ratio, it is possible to efficiently obtain a large output level up to the point where it peaks out.

[0042] Ideally, it would be suppressed just before hitting a plateau like the peak limiter in Figures 4 and 5 (see the thick dashed line (OUT(1:1)PK LIM)), but it is difficult to stop it suddenly mechanically. The same is true if the threshold value TH is raised too high; the headroom before hitting a plateau becomes smaller, so it is necessary to determine the balance with the physical vibration characteristics of the vibrator 12.

[0043] In this way, the signal adjustment unit 40 uses the magnetic force detected by the magnetic detection sensor 20 as the position of the vibrator 12, which is a permanent magnet, and controls the output level of the drive signal according to that value to control the position of the vibrator 12. In other words, as the vibrator 12 moves within the housing 10A in response to the input of the drive signal, the signal adjustment unit 40 detects the difference in magnetic force according to the positional relationship between the vibrator 12 and the magnetic detection sensor 20, and adjusts the output level of the drive signal.

[0044] <Operation of the vibration device according to the first embodiment of the technique of the present disclosure> The control unit 30 receives an input of a drive signal from the outside. The control unit 30 also receives an input of a sensor signal from the magnetic detection sensor 20. At this time, the control unit 30 repeatedly executes a vibration control process routine shown in FIG.

[0045] In step S100, the drive signal input unit 32 acquires an input drive signal.

[0046] In step S102, the sensor signal input unit 34 acquires an input sensor signal.

[0047] In step S104, the AD conversion unit 36 ​​performs AD conversion on the sensor signal received by the sensor signal input unit 34, and outputs a digital signal.

[0048] In step S106, the determination unit 38 determines whether or not the magnetic force detected by the magnetic detection sensor 20 is equal to or greater than a threshold value based on the output of the AD conversion unit 36. If the magnetic force detected by the magnetic detection sensor 20 is less than the threshold value, the process proceeds to step S110 without adjusting the drive signal. On the other hand, if the magnetic force detected by the magnetic detection sensor 20 is equal to or greater than the threshold value, the process proceeds to step S108.

[0049] In step S108, if it is determined that the magnetic force detected by the magnetic detection sensor 20 is equal to or greater than the threshold value, the signal adjustment unit 40 adjusts the level of the drive signal to be lowered.

[0050] In step S110, the drive circuit 42 outputs to the actuator 10 a control signal for driving the transducer 12 in accordance with the drive signal acquired in step S100 or the drive signal adjusted in step S108.

[0051] As described above, according to the vibration device according to the first embodiment of the technique of the present disclosure, the magnetic detection sensor detects the magnetic force corresponding to the displacement of the vibrator. The control unit adjusts the input drive signal according to the magnetic force, and vibrates the vibrator of the actuator based on the adjusted drive signal. This makes it possible to prevent the vibrator from coming into contact with the housing.

[0052] [Second embodiment] Next, a vibration device according to a second embodiment will be described. The same reference numerals will be used to designate the same components as those in the first embodiment, and the description thereof will be omitted.

[0053] In the second embodiment, the method of adjusting the drive signal is different from that in the first embodiment.

[0054] When the signal adjustment unit 40 of the control unit 30 of the vibration device 100 of the second embodiment determines that the magnetic force detected by the magnetic detection sensor 20 is equal to or greater than a threshold value, the signal adjustment unit 40 adjusts the level of the drive signal based on the magnetic force detected by the magnetic detection sensor 20 and the level of the drive signal.

[0055] Specifically, the level of the drive signal is adjusted according to a combination of the magnetic force detected by the magnetic detection sensor 20 and the current level of the drive signal.

[0056] More specifically, as shown in Table 1, when the magnetic force is "18" or more, the drive signal level is adjusted to be strongly suppressed. At this time, the drive signal level is adjusted to be strongly suppressed regardless of the current drive signal level.

[0057] Also, when the magnetic force is less than "18" and greater than or equal to "10", the drive signal level is adjusted to be suppressed according to the current drive signal level. At this time, if the drive signal level is high, the drive signal level is adjusted to be suppressed less. On the other hand, if the drive signal level is low, the drive signal level is adjusted to be suppressed more.

[0058] Moreover, when the magnetic force is less than "10", the level of the drive signal is not adjusted regardless of the current level of the drive signal. Alternatively, conversely, the level of the drive signal is adjusted to be increased according to the current level of the drive signal.

[0059] [Table 1]

[0060] Other configurations and operations of the vibration device 100 according to the second embodiment are similar to those of the first embodiment, and therefore will not be described.

[0061] As described above, according to the vibration device of the second embodiment, the magnetic detection sensor detects the magnetic force corresponding to the displacement of the vibrator. The control unit adjusts the input drive signal according to the combination of the magnetic force and the level of the drive signal, and vibrates the vibrator of the actuator based on the adjusted drive signal. This makes it possible to prevent the vibrator from coming into contact with the housing and to transmit vibrations appropriately.

[0062] [Third embodiment] Next, a vibration device according to a third embodiment will be described. The same reference numerals will be used to designate the same components as those in the first embodiment, and the description thereof will be omitted.

[0063] In the third embodiment, the method of adjusting the drive signal is different from the first and second embodiments.

[0064] When the magnetic force detected by the magnetic detection sensor 20 is determined to be equal to or greater than a threshold value, the signal adjustment section 40 of the control section 30 of the vibration device 100 according to the third embodiment specifies the movement direction and acceleration of the vibrator 12 based on the change per unit time of the magnetic force detected by the magnetic detection sensor 20. The signal adjustment section 40 adjusts the level of the drive signal to be suppressed based on the movement direction and acceleration of the vibrator 12.

[0065] Specifically, the level of the drive signal is adjusted to be suppressed according to a combination of the movement direction of the vibrator 12, the magnetic force, the level of the drive signal, and the acceleration.

[0066] More specifically, as shown in Table 2, when the motion direction of the vibrator 12 is a direction approaching the magnetic detection sensor 20 and the acceleration is large, the level of the drive signal is adjusted to be strongly suppressed (see FIG. 7A). At this time, the level of the drive signal is adjusted to be strongly suppressed regardless of the current level of the drive signal.

[0067] FIG. 7A shows an example in which, when the vibrator 12 is closer to the magnetic detection sensor 20 compared to the reference position (see the dashed line in FIG. 7A) and the acceleration of the vibrator 12 is large (see the hollow arrow mark in FIG. 7A), the level of the drive signal is adjusted to be strongly suppressed (see the dotted arrow mark in FIG. 7A).

[0068] When the movement direction of the vibrator 12 is a direction approaching the magnetic detection sensor 20 and the acceleration is small, the level of the drive signal is adjusted to be suppressed weakly (see FIG. 7B). FIG. 7B shows an example in which when the vibrator 12 is approaching the magnetic detection sensor 20 compared to the reference position (see the dashed dotted line in FIG. 7B) and the acceleration of the vibrator 12 is small (see the hollow arrow mark in FIG. 7B), the level of the drive signal is adjusted to be suppressed according to the current drive signal level (see the dotted arrow mark in FIG. 7B).

[0069] Furthermore, when the movement direction of the vibrator 12 is a direction approaching the magnetic detection sensor 20 and the acceleration is large, the level of the drive signal is adjusted to be suppressed weakly (see FIG. 7C). FIG. 7C shows an example in which the vibrator 12 moves away from the magnetic detection sensor 20 to the vicinity of the reference position (see the dashed dotted line in FIG. 7C) and the acceleration of the vibrator 12 is large (see the hollow arrow mark in FIG. 7C), and the level of the drive signal is adjusted to be suppressed according to the drive signal level (see the dotted arrow mark in FIG. 7C).

[0070] Furthermore, when the movement direction of the vibrator 12 is a direction toward the magnetic detection sensor 20 and the acceleration is small, the level of the drive signal is not adjusted (see FIG. 7D). Alternatively, conversely, the level of the drive signal is adjusted to be increased depending on the current level of the drive signal and the application. FIG. 7D shows an example in which the level of the drive signal is not adjusted when the vibrator 12 has moved away from the magnetic detection sensor 20 to the vicinity of the reference position (see the dashed dotted line in FIG. 7D) and the acceleration of the vibrator 12 is small (see the hollow arrow mark in FIG. 7D).

[0071] [Table 2]

[0072] In this way, the acceleration and motion direction of the vibrator 12 are identified, and the level of the drive signal is adjusted so that the vibrator 12 does not collide with the housing 10A. In the case of the magnetic detection sensor 20, the gradual increase or decrease in magnetic force is detected to identify the position and motion direction of the vibrator 12, the acceleration is calculated from the change in magnetic force per unit time, and the level of the drive signal is adjusted. This is done intermittently. The more frequently the adjustment is made, the more precise the control becomes.

[0073] Other configurations and operations of the vibration device 100 according to the third embodiment are similar to those of the first embodiment, and therefore will not be described.

[0074] As described above, according to the vibration device of the third embodiment, the magnetic detection sensor detects the magnetic force corresponding to the displacement of the vibrator. The control unit obtains the movement direction and acceleration of the vibrator based on the change in magnetic force, adjusts the input drive signal according to the combination of the movement direction and acceleration of the vibrator, and vibrates the vibrator of the actuator based on the adjusted drive signal. This makes it possible to prevent the vibrator from coming into contact with the housing.

[0075] In addition, in cases where vibrations are difficult to transmit despite the drive signal being at a high level, reverse adjustment can be performed to make the vibrations feel stronger. This is particularly effective not only for gaming applications, but also for applications where vibrations must be transmitted reliably, such as warnings.

[0076] [Fourth embodiment] Next, a vibration device according to a fourth embodiment will be described. The same reference numerals will be used to designate the same components as those in the first embodiment, and the description thereof will be omitted.

[0077] The fourth embodiment differs from the first to third embodiments in that a brake signal for stopping the vibration of the vibrator 12 is generated.

[0078] <Configuration of the vibration device according to the fourth embodiment of the technique of the present disclosure> As shown in FIG. 8, the control unit 430 includes a drive signal input unit 32, a sensor signal input unit 34, an AD conversion unit 36, a determination unit 38, a brake signal generation unit 440, and a drive circuit 42.

[0079] The brake signal generating unit 440 outputs a brake signal for stopping the driving of the vibrator 12 when it is determined that the magnetic force detected by the magnetic detection sensor 20 is equal to or greater than a threshold value.

[0080] Specifically, the brake signal generating unit 440 generates a signal opposite to the movement of the oscillator 12 or a signal with a DC component and outputs it as a brake signal in order to forcibly stop the vibration of the oscillator 12. The movement of the oscillator 12 is predicted from the change in the magnetic force detected by the magnetic detection sensor 20.

[0081] At this time, the brake signal generating unit 440 uses the magnetic force detected by the magnetic detection sensor 20 to generate a brake signal according to the value and controls the position of the vibrator 12. That is, the stronger the magnetic force, the more the brake signal is generated to forcibly stop the vibration of the vibrator 12.

[0082] The drive circuit 42 outputs a control signal for vibrating the vibrator 12 in response to the drive signal and the brake signal to the actuator 10. Specifically, the drive circuit 42 switches the drive signal to a brake signal and outputs a control signal to the actuator 10 to vibrate the vibrator 12.

[0083] <Operation of the vibration device according to the fourth embodiment of the technique of the present disclosure> The control unit 30 receives an input of a drive signal from the outside. The control unit 30 also receives an input of a sensor signal from the magnetic detection sensor 20. At this time, the control unit 30 repeatedly executes a vibration control process routine shown in FIG.

[0084] In step S100, the drive signal input unit 32 acquires an input drive signal.

[0085] In step S102, the sensor signal input unit 34 acquires an input sensor signal.

[0086] In step S104, the AD conversion unit 36 ​​performs AD conversion on the sensor signal received by the sensor signal input unit 34, and outputs a digital signal.

[0087] In step S106, the determination unit 38 determines whether or not the magnetic force detected by the magnetic detection sensor 20 is equal to or greater than a threshold value based on the output of the AD conversion unit 36. If the magnetic force detected by the magnetic detection sensor 20 is less than the threshold value, the process proceeds to step S402 without generating a brake signal. On the other hand, if the magnetic force detected by the magnetic detection sensor 20 is equal to or greater than the threshold value, the process proceeds to step S400.

[0088] In step S400, the brake signal generating unit 440 outputs a brake signal for stopping the driving of the vibrator 12.

[0089] In step S402, the drive circuit 42 outputs a control signal corresponding to the drive signal acquired in step S100 and the brake signal generated in step S400 to the actuator 10, thereby driving the actuator 10.

[0090] As described above, according to the vibration device of the fourth embodiment, the magnetic detection sensor detects the magnetic force corresponding to the displacement of the vibrator. The control unit generates a brake signal according to the magnetic force, and vibrates the vibrator of the actuator based on the drive signal and the brake signal. This makes it possible to prevent the vibrator from coming into contact with the housing.

[0091] [Fifth embodiment] Next, a vibration device according to a fifth embodiment will be described. The same reference numerals will be used to designate the same components as those in the first embodiment, and the description thereof will be omitted.

[0092] The fifth embodiment differs from the fourth embodiment in that a stop signal for stopping the output of a control signal to the actuator 10 is generated.

[0093] <Configuration of the vibration device according to the fifth embodiment of the technique of the present disclosure> As shown in FIG. 10, the control unit 530 includes a drive signal input unit 32, a sensor signal input unit 34, an AD conversion unit 36, a determination unit 38, a stop signal generation unit 540, and a drive circuit 42.

[0094] The stop signal generating unit 540 outputs a stop signal for stopping the output of a control signal to the actuator 10 when it is determined that the magnetic force detected by the magnetic detection sensor 20 is equal to or greater than a threshold value.

[0095] Specifically, the stop signal generating section 540 outputs a stop signal for stopping the output of the driving circuit 42 in order to stop the vibration of the vibrator 12.

[0096] The drive circuit 42 vibrates the vibrator 12 in response to the drive signal. At this time, the drive circuit 42 stops outputting the control signal to the actuator 10 when a stop signal is input.

[0097] <Operation of the vibration device according to the fifth embodiment of the technique of the present disclosure> The control unit 30 receives an input of a drive signal from the outside. The control unit 30 also receives an input of a sensor signal from the magnetic detection sensor 20. At this time, the control unit 30 repeatedly executes a vibration control process routine shown in FIG.

[0098] In step S100, the drive signal input unit 32 acquires an input drive signal.

[0099] In step S102, the sensor signal input unit 34 acquires an input sensor signal.

[0100] In step S104, the AD conversion unit 36 ​​performs AD conversion on the sensor signal received by the sensor signal input unit 34, and outputs a digital signal.

[0101] In step S106, the determination unit 38 determines whether or not the magnetic force detected by the magnetic detection sensor 20 is equal to or greater than a threshold value based on the output of the AD conversion unit 36. If the magnetic force detected by the magnetic detection sensor 20 is less than the threshold value, the process proceeds to step S502 without generating a stop signal. On the other hand, if the magnetic force detected by the magnetic detection sensor 20 is equal to or greater than the threshold value, the process proceeds to step S500.

[0102] In step S500, the stop signal generating unit 540 outputs a stop signal for stopping the output of the drive circuit .

[0103] In step S502, the drive circuit 42 vibrates the vibrator 12 in response to the drive signal acquired in the above step S100. At this time, the drive circuit 42 stops outputting the control signal to the actuator 10 when the stop signal output in the above step S500 is input.

[0104] As described above, according to the vibration device of the fifth embodiment, the magnetic detection sensor detects the magnetic force corresponding to the displacement of the vibrator, and the control unit generates a stop signal according to the magnetic force, and vibrates the vibrator of the actuator based on the drive signal and the stop signal. This makes it possible to prevent the vibrator from coming into contact with the housing.

[0105] [Sixth embodiment] Next, a vibration device according to a sixth embodiment will be described. The same reference numerals will be used to designate the same components as those in the first embodiment, and the description thereof will be omitted.

[0106] The sixth embodiment is different from the first embodiment in that the drive circuit performs feedback control by using a sensor signal as a feedback signal.

[0107] <Configuration of the vibration device according to the sixth embodiment of the technique of the present disclosure> As shown in FIG. 12, the control unit 630 of the vibration device 100 according to the sixth embodiment includes a drive signal input unit 32, a sensor signal input unit 34, and a drive circuit 642.

[0108] The sensor signal of the magnetic detection sensor 20 is returned as a feedback signal to the drive circuit 642. The drive circuit 642 compares the input drive signal with the input drive signal and outputs a control signal according to the difference to the actuator 10, thereby controlling the vibration of the vibrator 12 according to the magnetic force detected by the magnetic detection sensor 20.

[0109] <Operation of the vibration device according to the sixth embodiment of the technique of the present disclosure> The control unit 630 receives an input of a drive signal from the outside and also receives an input of a sensor signal from the magnetic detection sensor 20.

[0110] The drive signal input unit 32 acquires the input drive signal. The sensor signal input unit 34 acquires the input sensor signal. Then, the drive circuit 642 outputs a control signal to the actuator 10 according to the difference between the acquired drive signal and the acquired sensor signal, thereby driving the actuator 10.

[0111] As described above, according to the vibration device of the sixth embodiment, the magnetic detection sensor detects the magnetic force corresponding to the displacement of the vibrator, outputs a sensor signal, and the control unit uses the sensor signal as a feedback signal to vibrate the vibrator of the actuator, thereby preventing the vibrator from coming into contact with the housing.

[0112] In addition, the control configuration is simple and it is possible to apply a conventional feedback circuit. In addition, complex control programs and algorithms are not required. In addition, the sensor signal from the magnetic detection sensor is sent directly to the drive circuit, minimizing delays and enabling rapid control.

[0113] The feedback control described in the sixth embodiment may be applied to each of the first to fifth embodiments. Specifically, as shown in Fig. 2, Fig. 8, and Fig. 10, a sensor signal is output as a feedback signal from the sensor signal input unit 34 to the drive circuit 42. The drive circuit 42 outputs a control signal to the actuator 10 according to the difference between the acquired drive signal and the acquired sensor signal, thereby driving the actuator 10.

[0114] [Seventh embodiment] Next, a vibration device according to a seventh embodiment will be described. The same reference numerals will be used to designate the same components as those in the first embodiment, and the description thereof will be omitted.

[0115] The seventh embodiment differs from the first embodiment in that the output of the drive circuit is stopped at the timing when a sensor signal is acquired from the magnetic detection sensor.

[0116] <Configuration of the vibration device according to the seventh embodiment of the technique of the present disclosure> As shown in FIG. 13, the control unit 730 of the vibration device 100 of the seventh embodiment includes a drive signal input unit 32, a sensor signal input unit 34, an AD conversion unit 36, a judgment unit 38, a signal adjustment unit 40, a drive circuit 42, and a stop signal generation unit 740.

[0117] The stop signal generating unit 740 outputs a stop signal for stopping the output of the drive circuit 42 at the timing when the sensor signal input unit 34 acquires the sensor signal from the magnetic detection sensor 20 .

[0118] As a result, as shown in FIG. 14, the output of the control signal is stopped for a short period during which the magnetic force is measured (a period during which the movement of the transducer is not hindered), and the magnetic force is measured more accurately to identify the position of the transducer 12.

[0119] Other configurations and operations of the vibration device 100 according to the seventh embodiment are similar to those of the first embodiment, and therefore description thereof will be omitted.

[0120] The magnetic force measured by the magnetic detection sensor is considered to be the sum of the magnetic force of the vibrator including the permanent magnet and the magnetic force generated by the coil in the actuator. In order to detect the exact position of the vibrator, it is desirable to detect only the magnetic force of the vibrator. Therefore, in this embodiment, the influence of the magnetic force generated by the coil can be suppressed by stopping the output of the control signal during magnetic force measurement.

[0121] [Eighth embodiment] Next, a vibration device according to an eighth embodiment will be described. The same reference numerals will be used to designate the same components as those in the first embodiment, and the description thereof will be omitted.

[0122] The eighth embodiment differs from the first embodiment in that a magnetic detection sensor 20 is provided in the center of the side of the housing 10A and that a voice coil type actuator having a pair of coils is used to generate a control signal to the actuator to provide a traction force.

[0123] <Configuration of the vibration device according to the eighth embodiment of the technique of the present disclosure> As shown in Fig. 17, vibration device 800 includes actuator 901, magnetic detection sensor 20 provided on the surface of housing 10A, and control unit 900. In this embodiment, magnetic detection sensor 20 is provided on the side surface of housing 10A. Fig. 17 shows an example in which magnetic detection sensor 20 is provided in the center of the side surface of housing 10A.

[0124] As shown in FIG. 18A, the actuator 901 is mainly composed of a housing 10A forming an outer shell, an electromagnetic driving unit 3 provided within the housing 10A, a vibrator 12 that can be vibrated by the electromagnetic driving unit 3, a first support unit 5a and a second support unit 5b that elastically support both ends of the vibrator 12, and a first inner guide 6a and a second inner guide 6b that regulate the movement of the first support unit 5a and the second support unit 5b.

[0125] The housing 10A has a cylindrical housing main body, both open ends of which are closed by a first cover case 11a and a second cover case 11b.

[0126] The electromagnetic driving unit 3 has a cylindrical yoke 41 made of a soft magnetic material arranged inside the housing 10A, and a first coil 21a and a second coil 21b attached to the inner surface of the yoke 41 while being electrically insulated from the yoke 41.

[0127] The first coil 21a and the second coil 21b are wound around the inner surface of the yoke 41. The first coil 21a and the second coil 21b are each capable of generating a magnetic field when current is passed through a terminal.

[0128] The vibrator 12 is surrounded by the first coil 21a and the second coil 21b, and is disposed so as to vibrate along a vibration axis O. The vibrator 12 is composed of a disk-shaped magnet 50, a disk-shaped first pole piece 51a and a disk-shaped second pole piece 51b disposed so as to sandwich the magnet 50, and a first mass (weight, plummet) 52a and a second mass (weight, plummet) 52b disposed so as to sandwich the magnet 50, the first pole piece 51a, and the second pole piece 51b.

[0129] The magnet 50 is magnetized in the direction of the vibration axis O. The first pole piece 51a and the second pole piece 51b are made of a soft magnetic material and are attached to the magnet 50 by the magnetic attraction of the magnet 50 and adhesives or the like. The first mass 52a and the second mass 52b are made of a non-magnetic material and are attached to the first pole piece 51a and the second pole piece 51b by adhesives or the like. Therefore, the magnet 50, the first pole piece 51a, the second pole piece 51b, the first mass 52a, and the second mass 52b that constitute the vibrator 12 are integrated. The first mass 52a and the second mass 52b have flat contact surfaces with the first pole piece 51a and the second pole piece 51b. The surface opposite to this contact surface is formed in a spiral shape with the vibration axis O as the central axis and the tip parts 53a and 53b on the central axis protruding most outward.

[0130] In the vibrator 12 configured in this manner, both ends in the vibration axis O direction, that is, the tip ends 53a, 53b of the first mass 52a and the second mass 52b, respectively, are supported by the first support unit 5a and the second support unit 5b.

[0131] The first support unit 5a is composed of a first damper 60a (first leaf spring) and a first elastic member 61a provided on one surface of the first damper 60a.

[0132] The first damper 60a has a support portion 71a having a hole 70a formed in the center. The first damper 60a is connected to the vibrator 12 through the hole 70a. More specifically, the tip portion 53a of the first mass 52a is inserted into the hole 70a, and the tip portion 53a is pressed and crimped.

[0133] The first damper 60a also has three arms 72a that spirally extend from the support 71a to the outer periphery. The arms 72a are formed at equal intervals of 120° around the vibration axis O. The outer periphery of each arm 72a is connected to an annular frame 73a that runs along the inner surface of the housing body. The frame 73a is connected to flanges 13a that protrude radially inward at three locations on the inner surface of the housing body at 120° pitches around the vibration axis O.

[0134] The first damper 60a is made of one or more metal leaf springs, and in this embodiment, for example, a processed thin plate of stainless steel (spring material) is used. The material of the first damper 60a is not limited to metal, and may be a composite material containing resin or fiber. A material that is resistant to fatigue and has excellent flexibility is preferable.

[0135] The first damper 60a thus configured is elastically deformable within a predetermined range in the direction of the vibration axis O and in intersecting directions including a radial direction perpendicular to the vibration axis O. This predetermined range corresponds to the amplitude range of the vibrator 12 when normally used as the actuator 901. Therefore, the predetermined range is at least a range in which the first damper 60a does not come into contact with the housing 10A and a range in which the limit of elastic deformation of the first damper 60a is not exceeded.

[0136] The first elastic member 61a has a plate-like outer shape that conforms to the shape of the support portion 71a of the first damper 60a to a certain range of each arm portion 72a, and is fixed to one surface of the first damper 60a. The first elastic member 61a performs vibration damping of the first damper 60a by elastic deformation.

[0137] The second support unit 5b has the same configuration as the first support unit 5a, and includes a second damper 60b (second leaf spring) and a second elastic member 61b. In this embodiment, the second damper 60b and the first damper 60a have the same shape and are made of the same material, and the second elastic member 61b and the first elastic member 61a have the same shape and are made of the same material. The three arms 72b of the second damper 60b extend from the support part 71b in which the hole 70b is formed to the annular frame part 73b. The second damper 60b is connected to the vibrator 12 by inserting the tip part 53b of the second mass 52b into the hole 70b and crimping it. The second damper 60b is connected to three flanges 13b, each of which has an annular frame 73b protruding from the inner surface of the housing body, by inserting a boss 14b of the flanges 13b into a through hole formed in the frame 73b, and then being pressed and crimped. The spiral direction of each arm 72b of the second damper 60b is opposite to the spiral direction of each arm 72a of the first damper 60a. As a result, the vibrator 12 receives torques in opposite directions from the first damper 60a and the second damper 60b during vibration, and therefore does not rotate around the vibration axis O even if it is displaced in the direction of the vibration axis O.

[0138] The first inner guide 6a is provided on one side of the actuator 901 in the direction of the vibration axis O, and on the other side of the first support unit 5a in the direction of the vibration axis O (closer to the center of the housing 10A). The second inner guide 6b is provided on the other side of the actuator 901 in the direction of the vibration axis O, and on one side of the second support unit 5b in the direction of the vibration axis O (closer to the center of the housing 10A). In other words, the first inner guide 6a and the second inner guide 6b are provided closer to the center in the direction of the vibration axis O than the first support unit 5a and the second support unit 5b within the housing 10A.

[0139] As shown in FIG. 18B, when actuator 901 is in a state in which no current is applied to first coil 21a and second coil 21b, vibrator 12 supported by first damper 60a and second damper 60b is positioned in the center of first coil 21a and second coil 21b.

[0140] When vibrating the vibrator 12, an alternating current is passed through the first coil 21a and the second coil 21b in a direction that generates magnetic fields of opposite polarity alternately. That is, the same polarity is generated in adjacent portions of the first coil 21a and the second coil 21b.

[0141] For example, in the case of the polarity shown in Figure 18B, a thrust force is generated in the vibrator 12 toward the other side of the vibration axis O direction indicated by solid arrow A (to the right in Figure 18B), and if the current flowing through the first coil 21a and the second coil 21b is reversed, a thrust force is generated in the vibrator 12 toward one side of the vibration axis O direction indicated by dotted arrow B (to the left in Figure 18B).

[0142] In this manner, when an alternating current is applied to the first coil 21a and the second coil 21b, the vibrator 12 vibrates along the vibration axis O while receiving the biasing forces from the first damper 60a and the second damper 60b from both sides.

[0143] As shown in FIG. 19A, the first coil 21a and the second coil 21b are each connected to an independent external connection part 912, and the control unit 900 controls the level of the drive signal output to each independent external connection part 912 based on the detection information of the magnetic detection sensor 20.

[0144] For example, the control unit 900 senses the amplitude of the vibrator 12 based on the detection information of the magnetic detection sensor 20, and controls the levels of the drive signals output to the independent external connection units 912 so as to control the bias of the amplitude in the positive and negative directions. In this way, independent signal control of the first coil 21a and the second coil 21b enables high-precision and more complicated vibration control (such as presentation of traction force). This makes it possible to realize vibration expression such as traction force, resistance of an object surface, and fine unevenness of an object surface.

[0145] Here, the traction illusion is the unclear perception of a slowly changing acceleration due to the nonlinearity of perception. For example, the conditions for generating the illusion for the stimulus design are to apply vibration with an asymmetric waveform (similar to a sawtooth wave) in the time direction.

[0146] In addition, it is said that the vibration frequency range that is effective for the human body, such as traction illusion and vibration detection by biological tactile sensors (receptors), is low (100 Hz or less).

[0147] If the resonance frequency of actuator 901 is lowered while maintaining a high acceleration, the amount of vibration of the vibrator tends to increase, making it more likely to exceed the amplitude limit.

[0148] Furthermore, when the added mass due to gripping or the like fluctuates significantly, the amplitude increases further, making amplitude control even more important.

[0149] Therefore, in this embodiment, the magnetic detection sensor 20 monitors the amplitude amount and controls the vibration, thereby making it possible to avoid contact with the housing 10A and to drive at a low frequency.

[0150] In addition, since amplitude control can be performed by detecting the amount of displacement, it is possible to achieve this without a structure that requires mechanical amplitude restriction of the actuator. For example, vibration control is possible even if there is no cover case in the vibration direction.

[0151] The other configuration of the vibration device 800 is similar to that of the first embodiment, and therefore the description thereof will be omitted.

[0152] Also, vibration control may be performed in the same manner as the control unit 30 described in the first embodiment. In this case, the determination unit 38 of the control unit 30 determines whether or not the distance between the position of the vibrator 12 detected by the magnetic detection sensor 20 and the housing 10A is less than a threshold value based on the output of the AD conversion unit 36. If it is determined that the distance between the position of the vibrator 12 detected by the magnetic detection sensor 20 and the housing 10A is less than the threshold value, the signal adjustment unit 40 performs the following process. That is, the signal adjustment unit 40 adjusts the level of the drive signal so as to suppress it based on the distance between the position of the vibrator 12 detected by the magnetic detection sensor 20 and the housing 10A.

[0153] Also, vibration control may be performed in the same manner as the control unit 30 described in the second embodiment. In this case, the determination unit 38 of the control unit 30 determines whether or not the distance between the position of the vibrator 12 detected by the magnetic detection sensor 20 and the housing 10A is less than a threshold value based on the output of the AD conversion unit 36. If it is determined that the distance between the position of the vibrator 12 detected by the magnetic detection sensor 20 and the housing 10A is less than the threshold value, the signal adjustment unit 40 performs the following process. That is, the signal adjustment unit 40 adjusts the level of the drive signal according to a combination of the distance between the position of the vibrator 12 detected by the magnetic detection sensor 20 and the housing 10A, and the level of the drive signal.

[0154] Also, vibration control may be performed in the same manner as the control unit 30 described in the third embodiment. In this case, the determination unit 38 of the control unit 30 determines whether or not the distance between the position of the vibrator 12 detected by the magnetic detection sensor 20 and the housing 10A is less than a threshold value based on the output of the AD conversion unit 36. The signal adjustment unit 40 specifies the movement direction and acceleration of the vibrator 12 based on the change in the position of the vibrator 12 detected by the magnetic detection sensor 20, and adjusts the level of the drive signal to be suppressed based on the movement direction and acceleration of the vibrator 12.

[0155] Moreover, vibration control may be performed in the same manner as the control unit 430 described in the fourth embodiment. In this case, the brake signal generating unit 440 of the control unit 430 outputs a brake signal for stopping the driving of the vibrator 12 when the distance between the position of the vibrator 12 detected by the magnetic detection sensor 20 and the housing 10A is less than a threshold value.

[0156] Moreover, vibration control may be performed in the same manner as the control unit 530 described in the fifth embodiment. In this case, the stop signal generating unit 540 of the control unit 530 outputs a stop signal for stopping the output of a control signal to the actuator 10 when the distance between the position of the vibrator 12 detected by the magnetic detection sensor 20 and the housing 10A is less than a threshold value.

[0157] Also, vibration control may be performed in the same manner as the control unit 630 described in the sixth embodiment. In this case, the sensor signal of the magnetic detection sensor 20 is returned as a feedback signal to the drive circuit 642 of the control unit 630. The drive circuit 642 compares the input drive signal with the input drive signal and outputs a control signal according to the difference to the actuator 10, thereby controlling the vibration of the vibrator 12 according to the magnetic force detected by the magnetic detection sensor 20.

[0158] Moreover, vibration control may be performed in the same manner as the control unit 730 described in the seventh embodiment. In this case, the stop signal generating unit 740 of the control unit 730 outputs a stop signal for stopping the output of the drive circuit 42 at the timing when the sensor signal input unit 34 acquires the sensor signal from the magnetic detection sensor 20.

[0159] <Experimental Example> As an experimental example for examining the installation position of a magnetic sensor for detecting the position of a vibrator by detecting changes in leakage magnetic flux with a magnetic sensor, a magnetic field analysis was performed using FEMTET (registered trademark) to confirm the distribution of leakage magnetic flux.

[0160] Because the magnetic sensor only picks up the value of magnetic flux density in one axial direction, the magnetic flux density was evaluated not in terms of magnitude but in terms of the x component (radial direction) and z component (axial direction) (see FIG. 19A).

[0161] In the magnetic circuit having a pair of coils, a magnetic circuit of a magnet sandwiched between pole pieces with respect to a cylindrical yoke is used, and a neodymium magnet is used as the magnet constituting vibrator 12, and the configuration is symmetrical in the z-axis (axial) direction.

[0162] As shown in Fig. 19B, in a magnetic circuit having one coil, a permanent magnet is placed inside a pot-shaped yoke, and a ferrite magnet is used as the magnet constituting vibrator 12, with the configuration being asymmetric in the z-axis direction (up and down). The position of the yoke in the axial direction is not limited to the center of the case and is arbitrary, and is determined by the positional relationship with the coil and suspension. The top and bottom of the case are located in the axial direction of the pot-shaped yoke, and the coil is placed inside the pot-shaped yoke. The pot-shaped yoke is also open on the bottom side.

[0163] FIG. 20A shows, from the left, the magnitude, x component, and z component of magnetic flux relative to displacement at the center of the side surface of a housing of a magnetic circuit having a pair of coils.

[0164] FIG. 20B shows, from the left, the magnitude, x component, and z component of magnetic flux relative to displacement at the center of the top surface of the housing of a magnetic circuit having a pair of coils.

[0165] The x-component of the magnetic flux relative to the displacement at the center of the side of the housing changed as a linear function with no offset. Also, the z-component of the magnetic flux relative to the displacement at the center of the side of the housing changed as a quadratic function with a minimum at zero displacement.

[0166] In addition, the x-component of the magnetic flux relative to the displacement at the center of the top surface of the case changed as a linear function, there was an offset, and the offset amount was larger than the amount of change.In addition, the z-component of the magnetic flux relative to the displacement at the center of the top surface of the case changed as a linear function, there was an offset, and the offset amount was larger than the amount of change.

[0167] Therefore, it was found that in a magnetic circuit having a pair of coils, it is effective to detect the change in the x-component of the magnetic flux density at the center of the side surface of the housing.

[0168] FIG. 21A shows, from the left, the magnitude, x component, and z component of magnetic flux relative to displacement at the center of the side surface of a housing of a magnetic circuit having one coil.

[0169] FIG. 21B shows, from the left, the magnitude, x component, and z component of magnetic flux relative to displacement at the center of the top surface of the housing of a magnetic circuit having one coil.

[0170] FIG. 21C shows, from the left, the magnitude, x component, z component, and angle of magnetic flux relative to displacement at the center of the bottom surface of the housing of a magnetic circuit having one coil.

[0171] The x-component of the magnetic flux relative to the displacement at the center of the side of the housing changed as a linear function, there was an offset, and the offset amount was larger than the amount of change. Also, the z-component of the magnetic flux relative to the displacement at the center of the side of the housing changed as a linear function, there was an offset, and the offset amount was larger than the amount of change.

[0172] Additionally, the x component of the magnetic flux relative to the displacement at the center of the top surface of the case varied as a distorted quadratic function, reaching a maximum near the displacement of 0. Additionally, the z component of the magnetic flux relative to the displacement at the center of the top surface of the case varied as a linear function, with an offset that was greater than the amount of change.

[0173] In addition, the x-component of the magnetic flux relative to the displacement at the center of the bottom of the housing changed as a linear function, there was an offset, and the offset amount was larger than the amount of change.In addition, the z-component of the magnetic flux relative to the displacement at the center of the bottom of the housing changed as a linear function, there was an offset, and the offset amount was larger than the amount of change.

[0174] Thus, there were no positions or components at the center of the side, top, or bottom surfaces where changes in magnetic flux density could be easily detected.

[0175] Figure 21D shows, from left to right, the magnitude, x component, and z component of the magnetic flux versus displacement at a position a specified distance away from the center of the side of the housing of a magnetic circuit having one coil (a position on the side of the housing where the magnetic flux lines are parallel to the z direction (axial direction)).

[0176] The x-component of the magnetic flux with respect to the displacement 4 mm below the center of the side of the case varied as a linear function with no offset. Also, the z-component of the magnetic flux with respect to the displacement 4 mm below the center of the side of the case varied as a quadratic function and was minimal at a displacement of 0.

[0177] Therefore, it was found that in a magnetic circuit having one coil, it is effective to detect the change in the x-component of the magnetic flux density 4 mm below the center of the side of the housing.

[0178] Thus, it was found that arranging the magnetic sensor on the side of the case is more effective for detecting changes in the x-component of the magnetic flux density than arranging it on the top surface of the case. In other words, by arranging the magnetic sensor on the side of the case, the magnetic sensor can detect the displacement of the vibrator with high accuracy. It is most preferable to place the magnetic sensor at the position where the magnetic poles are reversed, but it does not have to be located in the center as long as it is on the side of the case.

[0179] According to the technology of the present disclosure, a displacement detection unit detects the displacement of the vibrator or the housing, and a control unit vibrates the vibrator based on an input drive signal and detection information from the displacement detection unit.

[0180] In this way, by detecting the displacement of the vibrator or the housing and vibrating the vibrator based on the detection information and the drive signal, it is possible to prevent the vibrator from coming into contact with the housing.

[0181] The displacement detection unit according to the technology disclosed herein is a magnetic detection sensor that detects magnetic force corresponding to the position of the vibrator, which changes in response to the input of the drive signal, and the control unit can control the level of a control signal for vibrating the vibrator in response to the drive signal based on the detection information from the displacement detection unit.

[0182] The control unit according to the technique of the present disclosure can control the level of the control signal based on the detection information of the displacement detection unit and the level of the drive signal.

[0183] The control unit of the technology disclosed herein can identify the movement direction and acceleration of the vibrator based on changes in the detection information of the displacement detection unit, and control the level of the control signal based on the movement direction and the acceleration.

[0184] The control unit according to the technique of the present disclosure can stop outputting the control signal in response to the detection timing by the displacement detection unit.

[0185] The control unit according to the technique of the present disclosure can control the level of the control signal by adjusting the level of the drive signal based on the detection information of the displacement detection unit.

[0186] The control unit according to the technique disclosed herein can adjust the level of the drive signal at a set compression ratio when the detected magnetic force exceeds a threshold value.

[0187] The control unit according to the technique disclosed herein can adjust the level of the drive signal by replacing the drive signal with a brake signal when the detected magnetic force exceeds a threshold value.

[0188] The control unit according to the technique disclosed herein can stop output of the control signal when the detected magnetic force exceeds a threshold value.

[0189] The control unit according to the technique of the present disclosure can control the level of the control signal by using the detected magnetic force as a feedback signal.

[0190] The magnetic detection sensor according to the technique of the present disclosure can be disposed on a side surface of the housing.

[0191] The vibration device according to the disclosed technique further includes a cylindrical electromagnetic driving unit provided inside the housing, and a pair of leaf springs respectively supporting one end and the other end of the vibrator in the vibration axis direction of the vibrator, the vibrator being provided radially inside the electromagnetic driving unit and supported so as to be able to vibrate along the vibration axis, the vibrator having a magnet whose magnetization direction is in the vibration axis direction, a pair of pole pieces made of a soft magnetic material that sandwich the magnet from both sides along the vibration axis, and a pair of weights made of a non-magnetic material that sandwich the pair of pole pieces from both sides along the vibration axis, the electromagnetic driving unit having a pair of coils each formed in a cylindrical shape and spaced apart along the vibration axis, and a cylindrical yoke made of a soft magnetic material that is arranged radially outside the pair of coils and formed to protrude outward in the vibration axis direction beyond the pair of coils, and the pair of coils can each be connected to an independent external connection unit.

[0192] The control unit according to the technique of the present disclosure can control the levels of the drive signals output to the respective independent external connection units based on the detection information of the displacement detection unit.

[0193] The technology of the present disclosure is not limited to the above-described embodiment, and various modifications and applications are possible without departing from the gist of the technology of the present disclosure.

[0194] Since the magnetic detection sensor detects a composite magnetic flux of the magnetic flux leaking from the drive coil and the magnetic flux of the vibrator, it is difficult to detect the displacement of the vibrator with high accuracy. Therefore, in the control unit according to this embodiment, the magnetic force from the drive coil of the actuator may be predicted from the drive signal, and the predicted magnetic force may be subtracted from the detection data of the magnetic detection sensor to more accurately calculate the magnetic flux of the vibrator. By calculating the magnetic flux of the vibrator more accurately, it is possible to detect the displacement of the vibrator with higher accuracy.

[0195] The technology disclosed herein may be applied to products that use multiple actuators (e.g., chairs, beds, floors, etc.). In this case, it is not necessary to provide a displacement detection unit for all actuators, but it is sufficient to provide a displacement detection unit for at least one actuator.

[0196] Further, in the above embodiment, a voice coil type actuator is used as the actuator, but the present invention is not limited to this, and an actuator other than a voice coil type actuator may be used.

[0197] In addition, although the magnetic detection sensor is used as the displacement detector for detecting the displacement of the vibrator, the present invention is not limited to this. A displacement detector for detecting the displacement of the housing may be used. For example, an electrostatic film sensor may be used to detect the deformation of the housing of the voice coil actuator, the magnitude of vibration, pressure on the device, etc., and the drive of the actuator may be controlled based on the detection result and the drive signal.

[0198] In addition, although the magnetic detection sensor is provided on the outside of the housing of the actuator, the present invention is not limited to this. For example, the magnetic detection sensor may be provided on the inside of the housing of the actuator. In this case, by incorporating the magnetic detection sensor itself inside the actuator, it is possible to achieve miniaturization and a constant positional relationship with the vibration element.

[0199] The control unit may also be configured to control the remaining vibration of the vibrator after the operation of vibrating the vibrator by the drive signal.

[0200] The disclosure of Japanese Application No. 2022-202447 is incorporated herein by reference in its entirety.

[0201] All publications, patent applications, and standards mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent application, or standard was specifically and individually indicated to be incorporated by reference.

Claims

1. A vibrator that provides vibration; A displacement detection unit that detects a displacement of the vibrator; A control unit that vibrates the transducer based on an input drive signal and detection information of the displacement detection unit; Including, The oscillator generates a magnetic flux, the displacement detection unit is a magnetic detection sensor that detects the magnetic flux, The magnetic detection sensor is disposed on a side surface of a housing, The control unit identifies the position of the vibrator based on the detected magnetic flux, and controls the level of a control signal for vibrating the vibrator in response to the drive signal based on the identified position of the vibrator and the distance from the housing.

2. A vibration device as described in claim 1, wherein the magnetic detection sensor is arranged on a side surface of the housing, the radial side surface intersecting the axial direction in which the vibrator vibrates.

3. A vibration device as described in claim 2, wherein the magnetic detection sensor detects changes in the radial magnetic flux.

4. A vibration device as described in claim 2, wherein the magnetic detection sensor is arranged at a position where the magnetic poles of the radial magnetic flux components are reversed.

5. The vibration device according to claim 1 , wherein the control unit controls a level of the control signal by adjusting a level of the drive signal based on the identified position of the vibrator and a distance between the vibrator and the housing.

6. The vibration device according to claim 5 , wherein the control unit adjusts a level of the drive signal at a set compression ratio when a distance between the specified position of the vibrator and the housing is less than a threshold value.

7. The vibration device according to claim 5, wherein the control unit, when a distance between the identified position of the vibrator and the housing is less than a threshold value, replaces the drive signal with a brake signal, and adjusts a level of the drive signal until the distance between the identified position of the vibrator and the housing exceeds the threshold value.

8. The vibration device according to claim 1 , wherein the control unit stops outputting the control signal until the detected magnetic flux falls within the threshold value when the distance between the identified position of the vibrator and the housing is less than a threshold value.

9. A sensor signal is output based on the detected magnetic flux, The vibration device according to claim 1 , wherein the control unit controls a level of the control signal based on a difference between the drive signal and the sensor signal.

10. The vibration device according to claim 1 , wherein the control unit identifies a motion direction and acceleration of the vibrator based on the identified change in position of the vibrator, and controls a level of the control signal based on the motion direction and the acceleration.

11. the control unit stops output of the control signal in response to a detection timing by the displacement detection unit; The vibration device according to claim 1 , wherein the position of the vibrator is identified based on the detected magnetic flux.

12. A sensor signal is output based on the detected magnetic flux, The vibration device according to claim 1 , wherein the control unit uses the sensor signal as a feedback signal to control a level of the control signal.

13. A cylindrical electromagnetic drive unit provided inside the housing; a pair of leaf springs supporting one end and the other end of the vibrator in a vibration axis direction of the vibrator, the vibrator is provided radially inside the electromagnetic drive unit and supported so as to be vibrated along a vibration axis; the vibrator includes a magnet whose magnetization direction is in the vibration axis direction, a pair of pole pieces made of a soft magnetic material sandwiching the magnet from both sides along the vibration axis, and a pair of weights made of a non-magnetic material sandwiching the pair of pole pieces from both sides along the vibration axis, the electromagnetic drive unit includes a pair of coils arranged at an interval along the vibration axis and each of which is formed into a cylindrical shape, and a cylindrical yoke made of a soft magnetic material arranged radially outside the pair of coils and formed to protrude outward in the vibration axis direction beyond the pair of coils, 2. The vibration device of claim 1, wherein each of the pair of coils is connected to an independent external connection.

14. The vibration device according to claim 13 , wherein the control unit controls levels of the drive signals output to the respective independent external connection units based on the detection information from the displacement detection unit.

15. A vibrator that provides vibration; A displacement detection unit that detects a displacement of the vibrator; A control unit that vibrates the transducer based on an input drive signal and detection information of the displacement detection unit; Including, The oscillator generates a magnetic flux, the displacement detection unit is a magnetic detection sensor that detects the magnetic flux, The control unit determines the movement direction and acceleration of the vibrator based on the change in magnetic flux detected by the displacement detection unit, and controls the level of a control signal for vibrating the vibrator in accordance with the drive signal based on the movement direction and the acceleration.

16. A vibrator that provides vibration; A displacement detection unit that detects a displacement of the vibrator; A control unit that vibrates the transducer based on an input drive signal and detection information of the displacement detection unit; Including, The oscillator generates a magnetic flux, the displacement detection unit is a magnetic detection sensor that detects the magnetic flux, the control unit controls a level of a control signal for vibrating the transducer in response to the drive signal, based on detection information from the displacement detection unit; Stopping output of a control signal for vibrating the transducer in response to the drive signal in response to a detection timing by the displacement detection unit; Identifying a position of the transducer based on the detected magnetic flux; A vibration device that controls a level of the control signal based on a position of the vibrator.

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