Vibration device and method for vibrating the same

Abstract

To provide a vibration device which can vibrate more strongly and a method for vibrating the vibration device.SOLUTION: In an IC card 1, a control circuit 20 includes: a micro computer 21 for generating a driving signal V2 in the shape of a square pulse; and a transistor 22 for boosting the driving signal V2 in the shape of a square pulse generated by the micro computer 21. As a driving signal for driving a piezoelectric element 18, a driving signal boosted by the transistor 22 is used. The driving signal generated by the transistor 22 is boosted higher than a driving signal V2 generated by the micro computer 21 so that improvement of the strength of vibrations of the piezoelectric element 18 can be attained.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to a vibration device and a vibration method thereof. [Background technology]

[0002] The following Cited Document 1 discloses a contactless IC card equipped with a vibration mechanism as a type of vibration device, and a piezoelectric element or a vibration motor is used as the vibration source of the vibration mechanism. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2014-132404 A Summary of the Invention [Problem to be solved by the invention]

[0004] The inventors have conducted extensive research into the vibration strength of vibration devices, and as a result have discovered a new technique for increasing the vibration strength.

[0005] An object of one aspect of the present disclosure is to provide a vibration device and a vibration method thereof that achieve improved vibration strength. [Means for solving the problem]

[0006] A vibration device according to one aspect of the present disclosure includes a power receiving unit that receives contactless power from a power supply apparatus, a control unit that generates a drive signal using the power received by the power receiving unit, and a piezoelectric vibrator that vibrates in response to the drive signal generated by the control unit, and the control unit includes a first control unit that generates a square pulse signal, and a second control unit that boosts the square pulse signal generated by the first control unit to generate the drive signal.

[0007] A vibration method for a vibration device according to one aspect of the present disclosure includes a power receiving unit that receives contactless power from a power supply device, a control unit that generates a drive signal from the power received by the power receiving unit, the control unit including a first control unit that generates a square pulse signal and a second control unit that boosts the square pulse signal generated by the first control unit to generate a drive signal, and a piezoelectric vibrator, in which the piezoelectric vibrator vibrates in response to the drive signal generated by the control unit.

[0008] In the above vibration device and vibration method thereof, the control unit includes a first control unit that generates a square pulse signal and a second control unit that boosts the square pulse signal generated by the first control unit, and the strength of vibration can be increased by using the signal boosted by the second control unit as a drive signal for driving the piezoelectric vibrator. Effect of the Invention

[0009] According to various aspects of the present disclosure, a vibration device and a vibration method thereof are provided, in which vibration strength is improved. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a schematic perspective view showing an IC card according to an embodiment. [Diagram 2] FIG. 2 is a diagram showing a state in which the IC card shown in FIG. 1 is held over a reader / writer. [Diagram 3] FIG. 3 is an exploded perspective view showing a layered structure of the IC card shown in FIG. [Figure 4] FIG. 4 is a diagram showing the vibration circuit of the IC card shown in FIG. [Diagram 5] FIG. 5 is a diagram showing the behavior of an IC card when power is being supplied appropriately. [Figure 6] FIG. 6 shows the behavior of an IC card when the power supply to the card is weak. [Figure 7] FIG. 7 is a diagram showing the behavior of an IC card when the power supply to the IC card is insufficient. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Various embodiments and examples will be described below with reference to the drawings. Note that the same or corresponding parts in each drawing are denoted by the same reference numerals, and duplicated explanations will be omitted.

[0012] An IC card 1 shown in FIG. 1 will be taken as an example of a type of vibration device. The IC card 1 has an IC module 10 built-in that performs arithmetic processing. The IC card 1 according to this embodiment is of a non-contact type, and has an antenna coil 16 built-in, which will be described later. As shown in FIG. 2, when the IC module 10 is held over a reader / writer 2, which is a type of power supply device (i.e., held in a state separated by a predetermined distance), power is supplied to the IC module 10 from the reader / writer 2 in a non-contact manner, and communication is performed between the IC module 10 and the reader / writer 2. In this specification, "non-contact power supply" includes not only power transmission, but also non-contact communication such as near field communication (NFC).

[0013] The IC card 1 has a plate-like outer shape and has a front surface 1a and a back surface 1b. An IC module 10 is exposed on the front surface 1a. The IC card 1 has a layered structure as shown in Fig. 3, in which a plastic plate 11, an antenna sheet 12, a base material 13, and a metal plate 14 are layered in this order from the back surface 1b side. The layers of the IC card 1 are bonded together with a known adhesive layer (e.g., a double-sided adhesive tape, an adhesive layer) not shown.

[0014] The plastic plate 11 is made of a resin material that does not impede magnetic flux. The surface of the plastic plate 11 forms the back surface 1b of the IC card 1. The metal plate 14 is made of a metal material such as stainless steel or titanium. The surface of the metal plate 14 forms the front surface 1a of the IC card 1. The IC module 10 is fitted into a partial area of ​​the metal plate 14.

[0015] The substrate 13 is a film made of an insulating resin material, and may be made of, for example, acrylic. The voltage regulator 15, the piezoelectric element 18, and the control circuit 20 are mounted on the substrate 13. The piezoelectric element 18 is a type of piezoelectric vibrator, and the piezoelectric vibrator may be made of only a piezoelectric element, or may be a combination of a piezoelectric element and a vibration plate. The vibration plate may be a plate made of resin, or may be a plate made of metal. In this embodiment, the piezoelectric element 18 is accommodated in a through hole provided in the substrate 13 and is adhered to the back surface 14a of the metal plate 14. By adhering and fixing the piezoelectric element 18 to the metal plate 14, the displacement and vibration of the piezoelectric element 18 are transmitted to the metal plate 14. That is, the vibration generated in the piezoelectric element 18 is transmitted from the inside of the IC card 1 to the surface portion, and is directly felt by the user of the IC card 1. The IC card 1 may be in a form in which it vibrates overall, or in which a part of the surface portion vibrates locally.

[0016] The antenna sheet 12 is made of an insulating resin material or a magnetic material. The antenna sheet 12 is provided with an antenna coil 16 including a coil pattern wound around the outer edge. The antenna coil 16 is electrically connected to the voltage regulator 15 of the substrate 13. The antenna coil 16 is magnetically connected to a coil included in the IC module 10 of the metal plate 14.

[0017] The IC card 1 has a vibration circuit 30 including the configuration shown in Fig. 4. That is, the IC card 1 has a power receiving unit 17 that receives contactless power from the reader / writer 2, a control circuit 20 (control unit) that generates a drive signal from the power received by the power receiving unit 17, and the vibration circuit 30 that includes a piezoelectric element 18 that vibrates in response to the drive signal generated by the control circuit 20.

[0018] The power receiving unit 17 includes the voltage regulator 15 and the antenna coil 16 described above, and receives contactless power from the reader / writer 2 to output two types of drive voltages. The control circuit 20 includes a microcomputer 21 (first control unit) and a transistor 22 (more specifically, a field effect transistor (FET) or a bipolar transistor) (second control unit). A drive voltage is applied from the power receiving unit 17 to each of the microcomputer 21 and the transistor 22. In this embodiment, of the two types of drive voltages output from the power receiving unit 17, the drive voltage V1 (+5V as an example) applied to the microcomputer 21 is lower than the drive voltage (+14V as an example) applied to the transistor 22. The high drive voltage applied to the transistor 22 can be output from a diode bridge included in the power receiving unit 17. The transistor 22 performs a switching operation by a square pulse-shaped drive signal V2 generated by the microcomputer 21, and generates a drive signal to be sent to the piezoelectric element 18. In response to a square pulse drive signal sent from a control circuit 20, the piezoelectric element 18 vibrates at an element drive voltage V3.

[0019] Next, the ideal drive voltage V1, drive signal V2, and element drive voltage V3 will be described with reference to Fig. 5. Fig. 5 shows the behavior of voltage, signal, and vibration, with the horizontal axis indicating the passage of time and the vertical axis indicating amplitude. Note that the ideal drive voltage V1, drive signal V2, and element drive voltage V3 are in a state where the distance between the IC card 1 and the reader / writer 2 is sufficiently short (for example, they are in direct contact with each other with no distance between them) and power is being properly supplied from the reader / writer 2 to the IC card 1.

[0020] In the state of FIG. 5, the drive voltage V1 applied from the power receiving unit 17 to the microcomputer 21 of the control circuit 20 is always kept at a constant value (for example, +5V). At this time, the microcomputer 21 of the control circuit 20 generates a drive signal V2 with an ideal rectangular pulse shape. Then, the piezoelectric element 18 vibrates at the element drive voltage V3 in response to the drive signal from the control circuit 20. Specifically, the piezoelectric element 18 expands (or contracts) at the timing t1 when the drive signal V2 rises, and gradually starts to contract (or expand) at the timing t2 when the drive signal V2 falls, vibrating by repeating such expansion and contraction. At this time, the period T (and the frequency 1 / T) of the piezoelectric element 18 is obtained by the interval of the expansion timing t1 (or the interval of the contraction start timing t2).

[0021] 6 shows the behavior of voltage, signal, and vibration when the distance between IC card 1 and reader / writer 2 is somewhat large (for example, 12 mm) and the power supply from reader / writer 2 to IC card 1 is weak. In the state of FIG. 6, drive voltage V1 applied from power receiving unit 17 to microcomputer 21 of control circuit 20 is not always constant, but is slightly lower than in the state of FIG. 5. Specifically, drive voltage V1 drops at timing t1 when piezoelectric element 18 expands. In addition, a voltage drop also occurs in drive signal V2 of control circuit 20. Piezoelectric element 18 vibrates with the same period T as in the state of FIG. 5, but the vibration intensity indicated on the vertical axis is lower than the intensity in the state of FIG. 5.

[0022] FIG. 7 shows the voltage, signal, and vibration behaviors when the distance between the IC card 1 and the reader / writer 2 is far (for example, more than 18 mm apart) and the power supply from the reader / writer 2 to the IC card 1 is insufficient. In the state of FIG. 7, the driving voltage V1 applied from the power receiving unit 17 to the microcomputer 21 of the control circuit 20 is not always a constant value and further decreases compared to the state of FIG. 6. Specifically, the driving voltage V1 significantly decreases at the timing t1 when the piezoelectric element 18 extends. As a result, a sufficient driving voltage V1 is not applied to the microcomputer 21 of the control circuit 20, and the microcomputer 21 temporarily stops at the timing t1 and resumes after the timing t2 when the driving voltage V1 returns. The intensity of the vibration of the piezoelectric element 18 shown on the vertical axis becomes lower than that in the state of FIG. 5. Due to the power shortage and the accompanying stop of the microcomputer 21, the piezoelectric element 18 has a weaker vibration intensity and an extended period T (i.e., a lower frequency) compared to the states of FIGS. 5 and 6.

[0023] In the IC card 1, the control circuit 20 includes a microcomputer 21 that generates a square pulse-shaped drive signal V2 and a transistor 22 that switches the square pulse-shaped drive signal V2 generated by the microcomputer 21. The drive voltage applied from the power receiving unit 17 to the transistor 22 can be output from the diode bridge included in the power receiving unit 17 and is at a higher voltage than the drive signal V1 sent from the power receiving unit 17 to the microcomputer 21. By switching the transistor 22 with the square pulse-shaped drive signal V2 generated by the microcomputer 21, the piezoelectric element 18 can be driven using an element drive voltage V3 that is higher (i.e., boosted) than the drive signal V2 output from the microcomputer 21 (V2 < V3), and an improvement in the vibration intensity of the piezoelectric element 18 can be realized.

[0024] In addition, in the IC card 1, the vibration pattern (first vibration pattern) of the piezoelectric element 18 when the distance between the reader / writer 2 and the power receiving unit 17 is short (first distance) is different from the vibration pattern (second vibration pattern) of the piezoelectric element 18 when the distance is longer than the first distance (second distance). In this embodiment, the first vibration pattern of the piezoelectric element 18 when the distance is short shown in FIG. 5 has a larger vibration intensity (amplitude) and a shorter period T than the second vibration pattern of the piezoelectric element 18 when the distance is long shown in FIG. 7. Therefore, the user can sense the difference in the distance between the IC card 1 and the reader / writer 2 (for example, whether it is the first distance or the second distance) from the difference in the vibration pattern. That is, the user can obtain information about the distance, and an increase in the amount of information transmitted to the user is realized.

[0025] As long as the first vibration pattern and the second vibration pattern are different, it is not necessary that both the amplitude and the period of the vibration are different, and only one of them may be different.

[0026] The square pulse signal generated by the microcomputer 21 may be a signal with a uniform pulse width, or may be a signal with a modulated pulse width (i.e., a PWM signal). By generating a PWM signal by the microcomputer 21, the vibration of the piezoelectric element 18, which vibrates in response to the drive signal of the control circuit 20, is modulated, and the piezoelectric element 18 can thereby produce a desired sound.

[0027] The present invention is not limited to the above-described embodiment, and can be modified in various ways. For example, the first control unit is not limited to a microcomputer, and may be an IC chip such as a timer IC. The second control unit is not limited to a FET, and may be another type of transistor. Furthermore, the vibration device is not limited to a card form, but may be in the form of various small items (fashion items, gadgets, accessories, etc.) The power supply device is not limited to a reader / writer, but may be a payment terminal or the like.

[0028] As can be understood from the above description, the present specification discloses the following. [Appendix 1] A power receiving unit that receives wireless power from a power supply device; A control unit that generates a drive signal using the power received by the power receiving unit; a piezoelectric vibrator that vibrates in response to a drive signal generated by the control unit; Equipped with A vibration device, wherein the control unit includes a first control unit that generates a square pulse signal, and a second control unit that boosts the square pulse signal generated by the first control unit to generate the drive signal. [Appendix 2] A vibration device as described in Appendix 1, wherein a first vibration pattern of the piezoelectric vibrator when the distance between the power supply device and a power receiving unit receiving power is a first distance is different from a second vibration pattern of the piezoelectric vibrator when the distance is a second distance longer than the first distance. [Appendix 3] The vibration device described in Appendix 2, wherein the first vibration pattern and the second vibration pattern differ in at least one of amplitude and period. [Appendix 4] 4. The vibration device of claim 3, wherein the amplitude of the first vibration pattern is greater than the amplitude of the second vibration pattern. [Appendix 5] 4. The vibration device of claim 3, wherein the period of the first vibration pattern is shorter than the period of the second vibration pattern. [Appendix 6] 6. The vibration device according to claim 1, wherein the vibration device is an IC card. [Appendix 7] 7. The vibration device according to claim 1, wherein the square pulse signal generated by the first control unit is a PWM signal. [Appendix 8] 8. The resonation device according to claim 1, wherein the second control unit includes a transistor. [Appendix 9] A vibration method for a vibration device comprising: a power receiving unit that receives contactless power from a power supply device; a control unit that generates a drive signal using the power received by the power receiving unit, the control unit including a first control unit that generates a square pulse signal and a second control unit that boosts the square pulse signal generated by the first control unit to generate the drive signal; and a piezoelectric vibrator, wherein the piezoelectric vibrator vibrates in response to the drive signal generated by the control unit. [Explanation of symbols]

[0029] 1...IC card, 2...reader / writer, 10...IC module, 17...power receiving unit, 18...piezoelectric element, 20...control circuit, 21...microcomputer, 22...transistor, 30...vibration circuit.

Claims

1. A power receiving unit that receives wireless power from a power supply device; A control unit that generates a drive signal using the power received by the power receiving unit; a piezoelectric vibrator that vibrates in response to a drive signal generated by the control unit; Equipped with A vibration device, wherein the control unit includes a first control unit that generates a square pulse signal, and a second control unit that boosts the square pulse signal generated by the first control unit to generate the drive signal.

2. The vibration device according to claim 1, wherein a first vibration pattern of the piezoelectric vibrator when the distance between the power supply device and a power receiving unit receiving power is a first distance is different from a second vibration pattern of the piezoelectric vibrator when the distance is a second distance longer than the first distance.

3. The vibration device according to claim 2 , wherein the first vibration pattern and the second vibration pattern are different in at least one of an amplitude and a period.

4. The vibration device of claim 3 , wherein an amplitude of the first vibration pattern is greater than an amplitude of the second vibration pattern.

5. The vibrating device according to claim 3 , wherein a period of the first vibration pattern is shorter than a period of the second vibration pattern.

6. The vibration device according to claim 1 , wherein the vibration device is an IC card.

7. The vibration device according to claim 1 , wherein the square pulse signal generated by the first control unit is a PWM signal.

8. The vibrating device of claim 1 , wherein the second control portion includes a transistor.

9. A vibration method for a vibration device comprising: a power receiving unit that receives contactless power from a power supply device; a control unit that generates a drive signal using the power received by the power receiving unit, the control unit including a first control unit that generates a square pulse signal and a second control unit that boosts the square pulse signal generated by the first control unit to generate the drive signal; and a piezoelectric vibrator, wherein the piezoelectric vibrator vibrates in response to the drive signal generated by the control unit.

Images