JP2004000925A - Linear vibration actuator apparatus, driving method for linear vibration actuator and electronic component using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the performance and the productivity of a linear vibration actuator apparatus. <P>SOLUTION: The linear vibration actuator 1 has a moving member 4A having a permanent magnet 5 in the inside diameter side and a coil part 2, and is constituted of a stator 3A opposed to the moving member in the outside diameter side and an elastic body 6 for connecting the stator and the moving member to each other. A driver is constituted of a driving part 22 having a switching element Q5 for energizing the coil part 2 by electricity, a control output part 27 for controlling the switching element and a zero crossing detecting part 25 detecting a zero crossing point of back electromotive force generated in the coil part and having the output fed back to the control output part. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a so-called linear vibration actuator device, a method of driving a linear vibration actuator device, and a portable information terminal using the same, which is an electromagnetic vibration generating device. Reliable and stable.
[0002]
[Prior art]
2. Description of the Related Art Vibration generators are used in information portable devices such as mobile phones for incoming calls. Conventionally, a cylindrical motor provided with an unbalanced weight has been used as the vibration generator. With a cylindrical motor, there is a limit to the reduction in thickness, and there is also difficulty in automation of mounting.
[0003]
To overcome these problems, coin type motors with unbalanced weights have been proposed and put to practical use. However, since the vibration direction is parallel to the printed circuit board, there is a problem that the vibration is hardly detected. Furthermore, a button-type linear vibration actuator has been proposed to generate vibration in the vertical direction with respect to the printed circuit board. However, it has been difficult to realize a large vibration force and a further reduction in thickness. Further, conventionally, a push-pull drive circuit generally including four switching elements has been used for driving the linear vibration actuator (for example, see Patent Document 1).
[0004]
FIG. 15 is a circuit configuration diagram of an example of such a circuit, in which a starting unit 61, a control output unit 62, a driving pulse setting unit 63, and a driving unit 64 in which four switching elements Q11 to Q14 are connected in a bridge configuration are used. The coil part 65 of the vibration actuator connected between the midpoints is operated. In addition to the large number of elements in the drive circuit, when moving the mover in both the positive direction and the negative direction, power is supplied to each of them, resulting in a problem that the control operation is complicated and power consumption is large. .
[0005]
Another prior art linear actuator is also disclosed. The present invention relates to a linear vibration actuator device having a novel configuration different from those of the related art, a driving method of the device, and an information portable terminal equipped with the device (for example, Patent Document 2, Patent Document 3, and Patent Document 4). reference).
[0006]
[Patent Document 1]
JP 2001-025706 A
[Patent Document 2]
JP 2001-520860 A
[Patent Document 3]
JP-A-2000-014190 (International Publication Number WO99 / 0673)
[Patent Document 4]
JP-A-11-197601
[0007]
[Problems to be solved by the invention]
An object of the present invention is to newly provide a configuration that is more rational than the configuration of the related art and the driving method thereof, and a driving method suitable for the configuration in order to improve the performance and productivity of the linear vibration actuator. As an issue.
[0008]
[Means for Solving the Problems]
In order to solve the above problems, the first invention according to the present application is:
In a linear vibration actuator device including a linear vibration actuator and a driver for driving the linear vibration actuator,
The linear vibration actuator,
(A) a mover having a permanent magnet magnetized in a radial direction;
(B) a stator having a coil portion and facing the permanent magnet;
(C) an elastic body that couples the stator and the mover and biases the mover toward the center of the stator;
The driver is
(D) a drive unit having a switching element for energizing the coil unit;
(E) a control output unit for controlling the switching element;
(F) a zero-crossing detection unit that detects a zero-crossing point of the back electromotive force generated in the coil unit and outputs a zero-crossing signal;
here,
The driver sends the zero-cross signal to the control output unit, energizes the coil unit in one direction, and vibrates the mover in cooperation with the elastic body.
[0009]
According to a second aspect of the present invention, in the linear vibration actuator device of the first aspect, the driver further includes a zero-cross monitoring unit interposed between the zero-cross detection unit and the control output unit.
[0010]
A third invention according to the present application is the linear vibration actuator device according to the second invention, wherein the zero-cross monitoring unit monitors the zero-cross signal and accepts the next zero-cross signal for a certain time after the zero-cross signal is input. Ban.
[0011]
According to a fourth aspect of the present invention, in the linear vibration actuator device of the first aspect, the driver sends a restart signal to the control output unit when the zero-cross signal is interrupted for a predetermined time.
[0012]
Further, according to a fifth aspect of the present invention, in the linear vibration actuator device of the first aspect, the zero-cross detecting unit is connected to the coil unit via a back electromotive force amplifying unit and a level shift unit. .
[0013]
According to a sixth aspect of the invention, in the linear vibration actuator device according to the first aspect, the driver further includes a timing adjustment unit interposed between the zero-cross detection unit and the control output unit.
[0014]
According to a seventh aspect of the present invention, in the linear vibration actuator device according to the sixth aspect, the timing adjustment unit includes a phase locked loop.
[0015]
According to an eighth aspect of the invention, in the linear vibration actuator device of the first aspect, the control output unit includes a pulse width modulation unit.
[0016]
A ninth invention according to the present application relates to a driving method of a linear vibration actuator,
Linear vibration actuators
A mover having a permanent magnet magnetized in a radial direction,
A stator having a coil portion and facing the permanent magnet;
An elastic body that couples the stator and the mover and biases the mover toward the center of the stator,
here,
(A) determining a zero crossing point of the back electromotive force generated by the coil unit;
(B) determining a time for energizing the coil unit for each cycle;
(C) determining a time for energizing the coil unit at the time of starting;
(D) starting counting in step (b) based on the determination result in step (a).
[0017]
A tenth invention according to the present application is the driving method for a linear vibration actuator device according to the ninth invention,
Further, there is provided a step (e) of starting counting based on the determination result of the step (a), and the determination result of the step (a) is invalidated until the count-up of the step (e).
[0018]
An eleventh invention according to the present application is the driving method for a linear vibration actuator device according to the ninth invention,
Further, a step (f) for starting counting based on the determination result of step (a) is provided, and the counting of step (c) is started by counting up the step (f).
[0019]
A twelfth invention according to the present application is the driving method for a linear vibration actuator device according to the eleventh invention,
Step (f) is reset by the next determination result of step (a).
[0020]
Further, the thirteenth invention according to the present application relates to a portable information terminal,
(A) a substrate;
(B) a linear vibration actuator mounted on the substrate;
(C) a driver mounted on the substrate,
The vibration actuator,
(B-1) a mover having a permanent magnet magnetized in a radial direction;
(B-2) a stator having a coil portion and facing the permanent magnet;
(B-3) an elastic body that connects the stator and the mover, and biases the mover toward the center of the stator;
The driver is
(C-1) a drive unit having a switching element for energizing the coil unit;
(C-2) a control output unit for controlling the switching element;
(C-3) a zero-crossing detecting unit that detects a zero-crossing point of the back electromotive force generated in the coil unit and outputs a zero-crossing signal;
here,
The driver sends the zero-cross signal to the control output unit, energizes the coil unit in one direction, and vibrates the mover in cooperation with the elastic body.
[0021]
According to a fourteenth aspect of the present application, in the information portable terminal of the thirteenth aspect, the linear vibration actuator generates a vibration having a maximum amplitude in a direction perpendicular to the substrate.
[0022]
In a fifteenth invention according to the present application, in the information portable terminal according to the thirteenth invention, the driver further includes a zero-cross monitoring unit interposed between the zero-cross detection unit and the control output unit.
[0023]
A sixteenth invention according to the present application is the information portable terminal according to the fifteenth invention, wherein the zero-cross monitoring unit monitors the zero-cross signal and prohibits receiving the next zero-cross signal for a certain time after the zero-cross signal is input. I do.
[0024]
According to a seventeenth aspect of the present application, in the information portable terminal of the thirteenth aspect, the driver sends a restart signal to the control output unit when the zero-cross signal is interrupted for a predetermined time.
[0025]
According to an eighteenth aspect of the present application, in the information portable terminal of the thirteenth aspect, the zero-cross detector is connected to the coil via a back electromotive force amplifier and a level shifter.
[0026]
In a nineteenth aspect according to the present application, in the information portable terminal according to the thirteenth aspect, the driver further includes a timing adjustment unit interposed between the zero-cross detection unit and the control output unit.
[0027]
According to a twentieth aspect of the present application, in the portable information terminal of the nineteenth aspect, the timing adjustment unit includes a phase locked loop.
[0028]
According to a twenty-first aspect of the present application, in the information portable terminal of the thirteenth aspect, the control output unit includes a pulse width modulation unit.
[0029]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0030]
(Embodiment 1)
FIG. 1 shows the configuration of a linear vibration actuator. The linear vibration actuator 1 has a mover 4A and a stator 3A. The mover 4A includes a polygonal outer yoke 4 and a permanent magnet 5 located inside the outer yoke 4. The stator 3A is located inside the mover 4A, and includes a cylindrical inner yoke 3 and a coil portion 2 having a winding wound around the inner yoke 3. The inner yoke 3 has teeth portions vertically. And a gap is present between the teeth.
[0031]
The permanent magnet 5 is unipolar magnetized such that the inner diameter and the outer diameter are different poles, for example, the inner diameter is N pole and the outer diameter is S pole. The inner yoke 3 and the outer yoke 4 are metallic substances formed by compacting magnetic powder. The inner yoke 3 and the outer yoke 4 may be formed by radial lamination of thin steel plates (lamination of thin steel plates around the shaft 8). Further, the inner yoke 3 and the outer yoke 4 may be formed of a formed body obtained by subjecting a steel plate to drawing. Further, the inner yoke 3 and the outer yoke 4 may be formed of a molded product obtained by subjecting a tubular steel material (a cylindrical steel material, a ring-shaped steel material) to a drawing process. Further, it may be constituted by a molded body of a resin material containing metal powder. As described above, the constituent materials and the constituent methods of the inner yoke 3 and the outer yoke 4 are various, but are not particularly limited.
[0032]
The inner yoke 3 has a shaft 8 at the center, and the shaft 8 protrudes from the bottom surface of the inner yoke 3. Then, the inner yoke 3 is positioned by the protrusion of the shaft 8 and the concave portion of the base 9, and is fixed on the base 9. The lower elastic body 6 is interposed between the base 9 and the inner yoke 3. The base 9 is made of a heat-resistant resin having a glass transition temperature of 90 degrees or more.
[0033]
The elastic body 6 is a ring-shaped thin spring plate, and two elastic bodies are provided above and below. The setting is such that when the mover 4A moves below the balance point, a force to move upward is given, and when the mover 4A moves above the balance point, a force to move downward is given. That is, the elastic body 6 urges the mover 4A to be located substantially at the center of the stator 3A.
[0034]
The coil section 2 is electrically connected to a metal land 11 extending from the bottom surface of the base 9, and power is supplied from the land 11. The land 11 may be provided on the top surface of the outer lid 7 instead of the bottom surface of the base 9.
[0035]
The outer lid 7 covers the stator 3A and the mover 4A, and is swaged and fixed by a cover swaging unit 10 provided on the base 9. The outer lid 7 avoids contact with other parts inside the actuator, protects the inside of the actuator during reflow processing, and facilitates handling of the actuator. The outer lid is made of metal, but may be made of heat-resistant resin.
[0036]
Such a linear vibration actuator 1 causes a current supplied from the land 11 to flow to the coil section 2 to generate a vibration magnetic flux. The mover 4A vibrates according to the oscillating magnetic flux.
[0037]
FIG. 2 shows a basic configuration of a driver for driving the linear vibration actuator.
[0038]
In FIG. 2, an activation unit 21 activates a linear vibration actuator such as an incoming signal in an information portable terminal, and is simulated by a switch 21A.
[0039]
The drive unit 22 connects the collector terminal of a switching element Q5 composed of an NPN transistor for driving the other end of the coil unit 2 having one end connected to the positive electrode of the circuit power supply Vcc, and connects its emitter terminal to the above circuit. It is connected to the negative electrode (ground potential) of the power supply Vcc. Then, it is input from the other end of the coil unit 2 to the zero cross detection unit 25 via the level shift unit 24 and the back electromotive force amplification unit 23, and detects the zero cross point of the back electromotive force of the coil unit. That is, the zero crossing point of the back electromotive force is to detect a point at which the amplitude of the vibration of the actuator 1 is maximum. This point is detected, and the signal is fed back to the control output unit 27. As a result, the operation of the drive unit 22 becomes reliable and stable.
[0040]
Next, the circuit operation of FIG. 2 will be described in detail. When the switch 21A of the activation unit 21 is turned on, the input terminal B of the one-shot multivibrator 33 receives the H signal, and the initial state of the input terminal A is L, so that the output terminal Q is set. An H-level pulse with a time width is output. This H-level pulse turns on the switching element Q5 via the OR circuit 27B, and the coil section 2 is energized. Although not shown, the one-shot multivibrator 33 has an input terminal for a time constant, and a capacitor and a resistor are connected to the input terminal for setting a time width.
[0041]
When the coil unit 2 is energized and the actuator is activated, a back electromotive force is generated from the coil unit 2 and is input to the zero cross detection unit 25 via the level shift unit 24 and the back electromotive force amplification unit 23. The level shift unit 24 has the purpose of adjusting the signal level of the back electromotive force waveform according to the power supply voltage Vcc. The level shift unit 24 is useful for unifying the circuit power supply Vcc, and the reference voltage of the back electromotive force amplifying unit 23 can be freely set to, for example, Vcc / 2 in accordance with the circuit power supply Vcc. it can.
[0042]
The zero-crossing detecting unit 25 compares the input from the back electromotive force amplifying unit 23 with the zero-crossing voltage and outputs the signal SX after inverting the input by the inverter 25B.
[0043]
The H level signal of the switch 21A and the signal SX are input to the input of the NAND element 32, and the signal SX is output. This signal SX is input to the AND element 26A of the zero-crossing detection monitoring unit 26. Since the initial state of the other input terminal of the AND element 26A is at the H level, the AND element 26A outputs a signal SY having the same logic level as SX.
[0044]
When the signal SY is input to the input terminal B of the one-shot multivibrator 27A of the control output unit 27 and the signal SY goes high, the output terminal Q of the one-shot multivibrator 27A outputs an H-level pulse SA having a set time width. Although not shown, the one-shot multivibrator 27A has an input terminal for a time constant, to which a capacitor and a resistor are connected to set a time width. This H-level pulse turns on the switching element Q5 via the OR element 27B and is input to the input terminal A of the one-shot multivibrator 26B of the zero-cross detection monitoring unit 26 at the same time.
[0045]
In the one-shot multivibrator 26B, since one input terminal B is fixed at the H level, the output terminal Q is set at the falling edge of the input signal of the input terminal B (from the H level to the L level) for a set time. An L-level pulse SM having a width is output. Although not shown, the one-shot multivibrator 26B has an input terminal for a time constant, to which a capacitor and a resistor are connected to set a time width. The L-level output of the one-shot multivibrator 26B is input to the AND element 26A to inhibit the SY signal. That is, the L level pulse has an effect of masking erroneous reading of the zero cross pulse. (Details will be described later.)
The one-shot multivibrator 31 outputs the signal of the output Q after a set time width from the rise of the signal when the signal SX from the zero-cross detection unit 25 disappears due to the linear vibration actuator stopping for some reason or the like. Becomes L. The falling signal (H level → L level) is input to the A input terminal of the one-shot multivibrator 33 as a trigger signal, and from this falling, an H pulse having a time width set by the one-shot multivibrator 33 is output. , The actuator will restart.
[0046]
When the switch 21A of the activation unit 21 is turned off, one input terminal of the NAND element 32 becomes L level, and the actuator stops.
[0047]
The diode D1 of the drive section 22 is for protecting the switching element Q5 when the back electromotive force from the coil section 2 becomes abnormally high.
[0048]
Although the driving unit 22 uses an NPN transistor for the output switching element Q5, it is of course possible to use a PNP transistor. In that case, the emitter of the PNP transistor is connected to the positive electrode of the circuit power supply Vcc, its collector is connected to one end of the winding, and the other end of the winding is connected to the negative electrode (ground potential) of the circuit power supply Vcc. Thus, the configuration may be such that the zero cross point of the back electromotive force is detected from one end of the winding.
[0049]
Next, the monitoring function (mask function) of the zero-cross detection signal will be described in detail with reference to FIGS. FIG. 3 shows a part of the monitoring function of the zero-cross detection signal in FIG. SB, SX, SM, SY, and SA are signals of each unit, and each correspond to the waveform in FIG.
[0050]
The back electromotive force waveform SB obtained from the coil unit 2 is shaped by the zero cross detection unit 25, and the waveform SX is output. Further, the waveform SX is output after being inverted by the NAND element 32 (not shown), but includes the hunting error signal in FIG. The waveform SM is a mask signal generated by the one-shot multivibrator 26B, and by feeding back to the AND element 26A, an erroneous signal is removed and a correct zero-cross signal SY is obtained. This SY signal is further output from the output terminal of the one-shot multivibrator 27A and input to the switching element Q5. As a result, the waveform of the signal SY and the waveform of the signal SA become equal, and SY = SA. In FIG. 4, the waveform of the signal SA is omitted, and only the waveform of the signal SY is shown.
[0051]
Next, the restart function will be described in detail with reference to FIGS. 5, 6A and 6B. FIG. 5 shows the restart function part in FIG. FIGS. 6A and 6B are timing diagrams of the zero-cross detection signal SY and the hold signal SH. FIG. 6A shows the case where the zero-cross signal is continuously detected, and FIG. 6B shows the case where the zero-cross signal detection fails. Is shown. As shown in FIG. 6B, when the zero-cross signal detection fails, the hold signal SH becomes L level after a certain period of time, so that the one-shot multivibrator 33 generates a restart pulse and restarts the actuator. .
[0052]
FIG. 7 is a signal processing flowchart of the first embodiment shown in FIG. Here, timers I, II, III, and IV, which are timing setting sections, correspond to the one-shot multivibrators 27A, 33, 26B, and 31 in FIG. 2, respectively. 10 shows the correspondence of the apparatus of the first embodiment in terms of software.
[0053]
Here, each timer performs the following purpose and operation.
[0054]
The timer I determines an operation pulse width, and determines an energization time to the coil unit 2 in each cycle. The counting is started when the back electromotive force is zero-cross determination Yes, and the energization of the coil unit 2 is stopped by counting up.
[0055]
The timer II determines the activation pulse width, and determines the energization time to the coil unit 2 at the time of activation. The count is started by the start signal, and the energization of the coil unit 2 is stopped by the count up.
[0056]
The timer III determines a mask pulse width, and starts counting from the count-up of the timer I, and masks the zero-cross determination until the count-up.
[0057]
The timer IV determines the hold pulse width, and starts counting when the zero-cross determination is Yes, and returns to the operation of the timer II when the time is up.
[0058]
Next, the flowchart of the signal processing of FIG. 7 will be described in detail. First, when the switch 21A of the activation unit 21 is turned on, the actuator drive command determination and the activation determination are Yes, and the timer II for outputting the actuator activation pulse is activated. A start pulse corresponding to the time width of the timer II is output to energize the coil unit 2, and the actuator forcibly starts driving. When the timer II counts up, the actuator start pulse output is turned off, and the energization of the coil portion of the actuator is stopped.
[0059]
Thereafter, the back electromotive force of the coil unit 2 is monitored, and if the zero-cross determination is Yes, the energization of the coil unit 2 is started again according to this determination, and the timer I and the timer IV start counting. When the timer I counts up, the power supply to the coil unit 2 is stopped, and at the same time, the timer III starts counting. When the timer III counts up, this loop is fed back to the start signal. If the zero-crossing determination becomes Yes again before the timer IV counts up, the count of the timer IV is reset. However, if the timer IV counts up without being reset, this loop is returned to the activation determination unit.
[0060]
That is, when the actuator is stopped due to the zero-cross determination failure, the coil section 2 is energized for restart. If there is no start signal, the control output unit is off and all the timers I to IV are stopped.
[0061]
By using the flowchart of FIG. 7, the above-described processing can be easily configured by software of a microcomputer. FIG. 8 shows an example of hardware in that case. For zero-cross detection of the back electromotive force from the coil unit 2 of the actuator, the back electromotive force is input to the microcomputer control unit 42 via the analog / digital (AD) conversion unit 41 to perform zero cross detection, The switching element is driven at the timing.
[0062]
If the back electromotive force is A / D converted and taken into a microcomputer or the like, any timing other than the zero crossing of the back electromotive force can be detected, and the timing of the drive pulse can be controlled at any position of the mover 4A. For example, the maximum value (positive or negative maximum value) of the amplitude of the back electromotive force is detected, and the driving pulse of the actuator is output. Experimentally, the output of the driving pulse at this timing has the highest efficiency.
[0063]
FIG. 9 is a time chart showing the positional relationship between the back electromotive force waveform and the mover 4A. The zero cross point of the back electromotive force is the maximum displacement point of the mover 4A. Further, a zero-cross point of the back electromotive force waveform appears when the phase of a quarter cycle is delayed from the zero-cross point of the mover 4A. At any of these timings, the switching element can be driven. However, when the switching element Q5 is turned on within a period including the zero cross point of the mover 4A, kinetic energy is given when the speed of the mover 4A is maximum. In this case, the driving can be performed most efficiently.
[0064]
As described above, the function of detecting the zero-crossing point of the back electromotive force of the coil unit 2 is provided, so that the mover 4A can be excited only in one direction by energizing the coil unit. That is, the forward movement of the mover 4A is performed by the electromagnetic force generated by energizing the coil unit 2, and the negative movement is performed only by the repulsive force and the attractive force of the elastic body 6, thereby achieving low power consumption. it can.
[0065]
Further, by directly using the back electromotive force generated from one end of the coil unit 2 for detecting the zero cross point of the back electromotive force, it is not necessary to add components for detection, and a simple configuration can be realized.
[0066]
(Embodiment 2)
FIG. 10 is a circuit configuration diagram according to the second embodiment of the present invention. The present embodiment is obtained by adding a pulse width modulation section 46 to the circuit configuration shown in FIG. 2, and is particularly effective when the coil resistance of the coil section 2 is small and a current flows too much when the switching element Q5 is turned on. It is. The pulse width modulation section 46 performs pulse width modulation of a signal from the control output section as an input signal of the switching element, thereby stabilizing the driving of the actuator and reducing power consumption.
[0067]
(Embodiment 3)
FIG. 11 is a circuit configuration diagram according to the third embodiment of the present invention. This embodiment is obtained by adding a timing adjustment unit 47 composed of a two-stage flip-flop circuit to the circuit configuration shown in FIG. As shown in the time chart of the waveform in FIG. 12, the switching element Q5 is turned on with a delay of time t from the zero cross point of the back electromotive force. As a result, the actuator drive pulse can be output at an arbitrary timing delayed from the back electromotive force zero cross point, and the actuator is driven at a position close to the zero cross point of the mover 4A, which has been experimentally confirmed to be efficient. can do.
[0068]
(Embodiment 4)
FIG. 13 is a circuit configuration diagram of Embodiment 4 of the present invention. This embodiment is obtained by adding a PLL section 48 as a timing adjustment section to the circuit configuration shown in FIG. Thereby, even when the resonance point of the actuator 1 fluctuates based on the zero-cross detection signal, a drive signal for the switching element Q5 can be stably generated at an arbitrary timing with respect to the vibration of the mover 4A.
[0069]
(Embodiment 5)
Next, as a device according to another embodiment of the present invention, an information portable terminal (for example, a mobile phone) equipped with the linear vibration actuator according to the present invention will be described. FIG. 14 is a sectional view of the structure. In FIG. 14, reference numeral 1 denotes the linear vibration actuator shown in FIG. 1, which is directly mounted on the device board 51 with its main axis (the shaft 8 in FIG. 1) vertical.
[0070]
In this actuator 1, terminal lands (lands 11 in FIG. 1) provided on the lower surface thereof are directly brazed to lands provided on the upper surface of the device board 51. A driver 52 of the linear vibration actuator 1 is mounted on the substrate 51 together with circuit components of the device. A battery 54 is housed in a housing 53 of the device 50, and power is supplied from the battery 54 to a circuit and a driver 52 of the device body. In this actuator, when power is supplied to the coil portion of the inner yoke, the outer yoke is attracted or repelled by the action of the magnetic field, and recoils by the action of the elastic leaf spring when the power supply to the coil portion stops. Vibrates so as to have a maximum amplitude in a direction perpendicular to the surface of the device board 51. By adopting an incoming signal as the activation signal of the actuator 1, the mobile phone can operate the actuator 1 and detect its vibration as an incoming signal of the maximum amplitude vibration on the sensing surface.
[0071]
According to the present invention, power supply to the coil portion of the actuator is controlled by ON / OFF operation of a single switching element, zero-cross detection of the back electromotive force of the coil portion is performed, and the signal is fed back to the control output portion. By doing so, the circuit configuration of the driver can be simplified, its operation can be made sure and stable, and the driving operation with low power consumption can be realized.
[0072]
Further, according to the method of the present invention, it is easy to realize the main system unit of the drive control unit of the actuator by microcomputer control, and it is possible to further reduce the size of the device.
[0073]
Furthermore, according to the present invention, a thin and highly efficient linear vibration actuator device and an information portable terminal can be provided, so that there are effects such as improvement of portability and improvement of battery durability.
[0074]
【The invention's effect】
ADVANTAGE OF THE INVENTION According to this invention, the high performance and productivity improvement of a linear vibration actuator apparatus can be aimed at, and industrial value is large. It is possible to newly provide a configuration that is more rational than the configuration of the related art and the driving method thereof, and a driving method that is suitable for the configuration, thereby contributing to the improvement of the performance of a device equipped with the present invention. It is useful for a small portable device or the like equipped with the present invention to be able to detect with a large vibration without using sound.
[Brief description of the drawings]
FIG. 1 is a sectional view of a linear vibration actuator according to a first embodiment of the present invention.
FIG. 2 is a circuit diagram of the driver.
FIG. 3 is a circuit diagram of a monitoring function part of the zero-cross detection signal.
FIG. 4 is an explanatory time chart of the above.
FIG. 5 is a circuit diagram of the zero-cross restart function part.
FIG. 6A is a time chart for explaining the same as the above (waveform diagram), and FIG. 6B is another time chart for explaining the same as the above (waveform diagram).
FIG. 7 is a signal processing flowchart of the driver.
FIG. 8 is a hardware configuration diagram of the above.
FIG. 9 is an explanatory time chart of the above.
FIG. 10 is a circuit diagram of a driver according to the second embodiment of the present invention.
FIG. 11 is a circuit diagram of a driver according to a third embodiment of the present invention.
FIG. 12 is an explanatory time chart of Embodiment 1;
FIG. 13 is a circuit diagram of a driver according to a fourth embodiment of the present invention.
FIG. 14 is a structural sectional view of an information portable terminal according to Embodiment 5 of the present invention.
FIG. 15 is a circuit configuration diagram of a conventional example.
[Explanation of symbols]
1 linear vibration actuator
2 Coil section
3 Inner yoke
3A stator
4 Outside yoke
4A mover
5 permanent magnet
6 Elastic body
7 outer lid
8 shaft
9 base
10 Lid caulking part
11 Land

Claims (21)

In a linear vibration actuator device including a linear vibration actuator and a driver for driving the linear vibration actuator,
The linear vibration actuator,
A mover having a permanent magnet magnetized in a radial direction,
A stator having a coil portion and facing the permanent magnet;
An elastic body that connects the stator and the mover and biases the mover toward the center of the stator, further comprising:
The driver is
A drive unit having a switching element that energizes the coil unit;
A control output unit that controls the switching element;
A zero-cross detection unit that detects a zero-cross point of the back electromotive force generated in the coil unit and outputs a zero-cross signal.
Then, the driver sends the zero-cross signal to the control output unit, energizes the coil unit in one direction, and vibrates the mover in cooperation with the elastic body. The linear vibration actuator device according to claim 1,
A linear vibration actuator device further comprising a zero-cross monitoring unit interposed between the driver and the zero-cross detection unit and the control output unit. The linear vibration actuator device according to claim 2,
A linear vibration actuator device having a configuration in which a zero-cross monitoring unit monitors a zero-cross signal and is prohibited from receiving a next zero-cross signal for a predetermined time after the input of the zero-cross signal. The linear vibration actuator device according to claim 1,
A linear vibration actuator device having a configuration in which a driver sends a restart signal to a control output unit when a zero-cross signal is interrupted for a predetermined time. The linear vibration actuator device according to claim 1,
A linear vibration actuator device including a configuration in which the zero-cross detection unit is connected to a coil unit via a back electromotive force amplification unit and a level shift unit. The linear vibration actuator device according to claim 1,
A linear vibration actuator device further comprising a timing adjustment unit in which the driver is interposed between the zero-cross detection unit and the control output unit. The linear vibration actuator device according to claim 6,
A timing adjustment unit is a linear vibration actuator device provided with a configuration including a phase locked loop. The linear vibration actuator device according to claim 1,
A linear vibration actuator device in which the control output unit includes a configuration including a pulse width modulation unit. In the driving method of the linear vibration actuator,
The linear vibration actuator,
A mover having a permanent magnet magnetized in a radial direction,
A stator having a coil portion and facing the permanent magnet;
An elastic body that couples the stator and the mover and biases the mover toward the center of the stator,
Further, the linear vibration actuator is
(A) determining a zero crossing point of the back electromotive force generated by the coil unit;
(B) determining a time for energizing the coil unit for each cycle;
(C) determining a time for energizing the coil unit at the time of starting;
(D) a step of starting counting in step (b) based on the determination result in step (a). The method for driving a linear vibration actuator according to claim 9,
The method of driving a linear vibration actuator further comprises a step (e) of starting counting based on the determination result of the step (a), and invalidating the determination result of the step (a) until the count-up of the step (e). The method for driving a linear vibration actuator according to claim 9,
Further, there is provided a step (f) of starting counting based on the determination result of step (a), and the driving method of the linear vibration actuator, wherein the counting of step (c) is started by counting up the step (f). The driving method of a linear vibration actuator according to claim 11,
Step (f) is a method of driving the linear vibration actuator that is reset according to the result of the determination following step (a). In portable information terminals,
A substrate, having a linear vibration actuator mounted on the substrate, and a driver mounted on the substrate,
The vibration actuator,
A mover having a permanent magnet magnetized in a radial direction, a stator having a coil portion, facing the permanent magnet, connecting the stator and the mover, and fixing the mover An elastic body that biases the center of the child,
The driver is
A drive unit having a switching element that energizes the coil unit, a control output unit that controls the switching element, a zero cross point of a back electromotive force generated in the coil unit, and a zero cross detection unit that outputs a zero cross signal. Has,
Furthermore, the driver sends the zero-cross signal to the control output unit, energizes the coil unit in one direction, and vibrates the mover in cooperation with the elastic body. The information portable terminal according to claim 13,
An information portable terminal, wherein the linear vibration actuator generates a vibration having a maximum amplitude in a direction perpendicular to the substrate. The information portable terminal according to claim 13,
The information portable terminal further includes a zero-cross monitoring unit interposed between the driver and the zero-cross detection unit and the control output unit. The information portable terminal according to claim 15,
An information portable terminal that monitors a zero-cross signal and prohibits receiving a next zero-cross signal for a certain period of time after the zero-cross signal is input. The information portable terminal according to claim 13,
The information portable terminal, wherein the driver sends a restart signal to the control output unit when the zero-cross signal is interrupted for a predetermined time. The information portable terminal according to claim 13,
An information portable terminal, wherein the zero cross detection unit is connected to the coil unit via a back electromotive force amplification unit and a level shift unit. The information portable terminal according to claim 13,
An information portable terminal, further comprising a timing adjustment unit in which the driver is interposed between the zero-cross detection unit and the control output unit. The information portable terminal according to claim 19,
The timing adjustment unit is an information portable terminal including a phase locked loop. The information portable terminal according to claim 13,
The control output unit is an information portable terminal including a pulse width modulation unit.

Images