CN110199345A - Audio device, sound controller and program - Google Patents
Audio device, sound controller and program Download PDFInfo
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- CN110199345A CN110199345A CN201880005537.3A CN201880005537A CN110199345A CN 110199345 A CN110199345 A CN 110199345A CN 201880005537 A CN201880005537 A CN 201880005537A CN 110199345 A CN110199345 A CN 110199345A
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- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10K—SOUND-PRODUCING DEVICES; METHODS OR DEVICES FOR PROTECTING AGAINST, OR FOR DAMPING, NOISE OR OTHER ACOUSTIC WAVES IN GENERAL; ACOUSTICS NOT OTHERWISE PROVIDED FOR
- G10K9/00—Devices in which sound is produced by vibrating a diaphragm or analogous element, e.g. fog horns, vehicle hooters or buzzers
- G10K9/12—Devices in which sound is produced by vibrating a diaphragm or analogous element, e.g. fog horns, vehicle hooters or buzzers electrically operated
- G10K9/122—Devices in which sound is produced by vibrating a diaphragm or analogous element, e.g. fog horns, vehicle hooters or buzzers electrically operated using piezoelectric driving means
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- Piezo-Electric Transducers For Audible Bands (AREA)
- Circuit For Audible Band Transducer (AREA)
Abstract
The acoustic pressure for the sound that the project of the disclosure is to make the piezoelectric element in audio device to issue is not easy to reduce.Audio device (1) has piezoelectric element (11) and control unit (14).Piezoelectric element (11) receives periodic driving voltage and vibrates, thus the sound of output acoustic pressure corresponding with driving voltage.Control unit (14) controls driving voltage.Control unit (14) controls driving voltage in a manner of the fixed cycle (T0) for repeating to include first period (T1) and the second phase (T2).First period (T1) is during making sound of piezoelectric element (11) output as the first acoustic pressure of benchmark.During the second phase (T2) is the sound for making piezoelectric element (11) and exporting according to the environment temperature for being placed with piezoelectric element (11) the second acoustic pressure lower than the first acoustic pressure.
Description
Technical field
The present disclosure relates generally to a kind of audio device, sound controller and programs, and in more detail, being related to one kind makes
With the audio device of piezoelectric element, sound controller and program.
Background technique
One kind is disclosed in patent document 1 to have to sounding body offer with the letter of same period switching duty cycle (DUTY ratio)
Number come make sound pressure variations structure ring move device (audio device).Ring described in patent document 1 is moved device and is had: generation sound
The sounding body of sound；It is enough to drive the sounding body driving amplifier of the horizontal electric current of sounding body for supplying；And acoustic pressure control
Circuit.Acoustic pressure control circuit controls signal according to acoustic pressure to switch the duty ratio of the dynamic signal of sound ring.
Device is moved in the ring described in patent document 1, for example, driving hair so that acoustic pressure is set as maximum state
In the case where sound body (piezoelectric element), may cause following problems: due to be placed with piezoelectric element environment temperature rise and
The acoustic pressure for the sound for causing piezoelectric element to issue reduces.
Existing technical literature
Patent document
Patent document 1: Japanese Unexamined Patent Publication 11-153994 bulletin
Summary of the invention
The disclosure is to complete in view of the above problems, and its purpose is to provide the piezoelectric element hairs in a kind of audio device
The acoustic pressure of sound out is not easy reduced audio device, sound controller and program.
Audio device involved in one mode of the disclosure has piezoelectric element and control unit.Piezoelectric element receives the period
Property driving voltage and vibrate, thus the sound of corresponding with the driving voltage acoustic pressure of output.Control unit controls driving voltage.
Control unit controls driving voltage in a manner of the fixed cycle for repeating to include first period and the second phase.First period is to make to press
During sound of the electric device output as the first acoustic pressure of benchmark.The second phase is to keep piezoelectric element first according to piezoelectricity is placed with
During sound of the temperature of the environment of part to export the second acoustic pressure lower than the first acoustic pressure.
Sound controller involved in one mode of the disclosure controls the driving voltage for being applied to piezoelectric element, the pressure
Electric device receives periodic driving voltage and vibrates, thus the sound of output acoustic pressure corresponding with driving voltage.Sound equipment
Control device has the function that driving voltage is controlled in a manner of the fixed cycle for repeating to include first period and the second phase.The
It is during making sound of the piezoelectric element output as the first acoustic pressure of benchmark during one.The second phase be make piezoelectric element according to
The temperature of the environment of piezoelectric element is placed with come during exporting the sound of the second acoustic pressure lower than the first acoustic pressure.
Program involved in one mode of the disclosure is the program for controlling the driving voltage for being applied to piezoelectric element,
The piezoelectric element receives periodic driving voltage and vibrates, thus the sound of output acoustic pressure corresponding with driving voltage.
Program makes computer system execute following processing: being controlled in a manner of the fixed cycle for repeating to include first period and the second phase
Driving voltage.First period is during making sound of the piezoelectric element output as the first acoustic pressure of benchmark.The second phase
It is the sound for making piezoelectric element and exporting second acoustic pressure lower than the first acoustic pressure according to the temperature for the environment for being placed with piezoelectric element
During.
Detailed description of the invention
The A of Fig. 1 is the block diagram for indicating the Sketch of audio device involved in an embodiment of the disclosure.Fig. 1
B be the concept map for indicating the variation of the driving frequency in the audio device.
Fig. 2 is the figure for indicating the Sketch of driving circuit and piezoelectric element in the audio device.
The A of Fig. 3 is indicated in the audio device, is 50% in the duty ratio of the first driving signal and the second driving signal
In the case where driving voltage waveform figure.The B of Fig. 3 is indicated in the audio device, in the first driving signal and second
The duty ratio of driving signal be 40% in the case where driving voltage waveform figure.
Fig. 4 is the first driving signal and second in the audio device, in the case where environment temperature is the first stage
The waveform diagram of driving signal.
The A of Fig. 5 is the within the second phase in the audio device, in the case where environment temperature is second stage
The waveform diagram of one driving signal and the second driving signal.The B of Fig. 5 is in the audio device, is the phase III in environment temperature
In the case where the first driving signal and the second driving signal within the second phase waveform diagram.
The A of Fig. 6 is the within the second phase in the audio device, in the case where environment temperature is fourth stage
The waveform diagram of one driving signal and the second driving signal.The B of Fig. 6 is in the audio device, is the 5th stage in environment temperature
In the case where the first driving signal and the second driving signal within the second phase waveform diagram.
Fig. 7 is the first driving signal and second in the audio device, in the case where environment temperature is fourth stage
Other waveform diagrams of driving signal.
Specific embodiment
(1) summary
In the following, illustrating the summary of the audio device 1 of present embodiment using the B of the A of Fig. 1 and Fig. 1.Present embodiment
Audio device 1 is a kind of device for exporting sound (for example, alarm tone).As shown in the A of Fig. 1, audio device 1 has piezoelectric element
11 and control unit 14.
Piezoelectric element 11 receives periodic driving voltage V1 (referring to Fig. 2) and vibrates, thus output and driving electricity
Press the sound of the corresponding acoustic pressure of V1.In the present embodiment, piezoelectric element 11, which is worked as from aftermentioned driving circuit 13, receives rectangular wave
It is vibrated when the driving voltage V1 of shape because of piezoelectric effect, to export the size (amplitude) with driving voltage V1 and receive drive
The sound of the time corresponding acoustic pressure of dynamic voltage V1.
Control unit 14 controls driving voltage V1.In the present embodiment, control unit 14 is by controlling aftermentioned booster circuit
12 control the size of driving voltage V1.In addition, control unit 14 controls accounting for for driving voltage V1 by control driving circuit 13
Empty ratio, that is to say, that control the time for applying driving voltage V1 to piezoelectric element 11.
Moreover, control unit 14 is as shown in the B of Fig. 1 to repeat the fixed cycle including first period T1 and second phase T2
The mode of T0 controls driving voltage V1.First period T1 is the sound for making the output of piezoelectric element 11 as the first acoustic pressure of benchmark
Period.In the present embodiment, the first acoustic pressure is, for example, 11 energy of piezoelectric element when assuming that aftermentioned driving frequency is fixed
The maximum acoustic pressure enough exported.Second phase T2 is to make piezoelectric element 11 according to being placed with the environment temperature of piezoelectric element 11 come defeated
Out during the sound of the second acoustic pressure lower than the first acoustic pressure.That is, in second phase T2, what piezoelectric element 11 exported
The rising tone changes according to environment temperature at all.
" environment temperature " described in the disclosure can be the temperature of piezoelectric element 11 itself.In addition, for example in piezoelectric element
In the case that 11 are incorporated in shell, " environment temperature " described in the disclosure, either the intracorporal temperature of shell, is also possible to
Temperature outside shell.That is, " environment temperature " as long as either directly or indirectly indicate piezoelectric element 11 itself temperature
Temperature.
As described above, in the present embodiment, piezoelectric element 11 exports in the first period T1 in fixed cycle T0
The sound of one acoustic pressure exports the sound of second acoustic pressure lower than the first acoustic pressure in second phase T2 according to environment temperature.Cause
And in the present embodiment, it has the advantage that and for example persistently exports what piezoelectric element 11 can export with piezoelectric element 11
The case where sound of maximum acoustic pressure, is compared, and the rising of environment temperature is able to suppress, and piezoelectric element 11 exports from the results of view
Sound is not easy to reduce.
(2) detailed content
In the following, illustrating the audio device 1 of present embodiment using the B of A~Fig. 3 of Fig. 1.The sound equipment of present embodiment fills
It sets 1 and has piezoelectric element 11, booster circuit 12, driving circuit 13, control unit 14 and temperature sensor 15.In present embodiment
In, piezoelectric element 11, booster circuit 12, driving circuit 13, control unit 14 and temperature sensor 15 are incorporated in common
In shell.Moreover, the sound that piezoelectric element 11 exports for example is output to the outside of shell by the sound hole being arranged on shell.
Piezoelectric element 11 is piezoelectric buzzer, as shown in Fig. 2, the piezoelectric element 11 is the thickness direction in oscillating plate 113
On two faces on be respectively set the first piezoelectric board 111 and the second piezoelectric board 112 bimorph (bimorph) type piezoelectricity
Element.The first switching element Q1 of first piezoelectric board 111 and the second piezoelectric board 112 and aftermentioned driving circuit 13 is switched with third
Tie point electrical connection between element Q3.In other words, the first piezoelectric board 111 and the second piezoelectric board 112 are via first switch member
Part Q1 to be electrically connected on high-tension side one end of booster circuit 12.The second switch of oscillating plate 113 and aftermentioned driving circuit 13
Element Q2 is the same as the tie point electrical connection between the 4th switch element Q4.In other words, oscillating plate 113 is via the 4th switch element Q4
To be electrically connected with one end of the low-pressure side of booster circuit 12 (reference potential).In addition, oscillating plate 113 because of the first piezoelectric board 111 and
It is applied the wavy driving voltage V1 of rectangle between second piezoelectric board 112 and oscillating plate 113 and vibrates.Moreover, piezoelectricity is first
Part 11 vibrates to export the sound of acoustic pressure corresponding with driving voltage V1 according to driving voltage V1 by oscillating plate 113.
Booster circuit 12 is DC/DC converter, which increases the DC voltage being entered, and electric to driving
DC voltage after the output raising of road 13.Booster circuit 12 includes switch element.Moreover, booster circuit 12 is based on from aftermentioned
The control signal of control unit 14 is corresponding big switching over to the on/off of switch element, thus exporting and controlling signal
Small DC voltage.In the present embodiment, the straight of the battery from the power supply as audio device 1 is inputted to booster circuit 12
Galvanic electricity pressure.
As shown in Fig. 2, driving circuit 13 is by the inverter of four switch element Q1~Q4 bridge-type constituted.In the following,
Four switch element Q1~Q4 are also referred to as " first switching element Q1 ", " second switch element Q2 ", " third switch element
Q3 " and " the 4th switch element Q4 ".Driving circuit 13 is based on the first driving signal S1 and from aftermentioned control unit 14
Two driving signal S2 switches over the on/off of switch element Q1~Q4, thus by the output voltage of booster circuit 12
It is transformed to the wavy driving voltage V1 of rectangle, and driving voltage V1 is applied to piezoelectric element 11.First driving signal S1 and second
Driving signal S2 is PWM (Pulse Width Modulation: pulsewidth modulation) signal, and phase differs 180 degree each other.Cause
And piezoelectric element 11 is alternately applied the output voltage of booster circuit 12 and the electricity after inverting the polarity of the output voltage
Pressure.
Control unit 14 using processor and memory as the microcomputer of main structure for example by being constituted.That is, control
It is realized by the computer system with processor and memory in portion 14.Moreover, by executing program appropriate by processor,
Computer system is functioned as control unit 14.Program both can it is pre-recorded in memory, can also be by because of spy
It is provided in the recording mediums of the electrical communication lines to provide or be recorded in the non-transitories such as storage card such as net.
Control unit 14 controls driving voltage V1 by control booster circuit 12 and driving circuit 13.Specifically, control
The switch element that portion 14 is included to booster circuit 12 provides control signal S0, is controlled by making switching elements ON/disconnection
The size of the output voltage of booster circuit 12.The maximum of the size of the size and driving voltage V1 of the output voltage of booster circuit 12
It is worth roughly equal.In addition, control unit 14 provides first to the first switching element Q1 and the 4th switch element Q4 of driving circuit 13
Driving signal S1, and the second driving signal is provided to the second switch element Q2 and third switch element Q3 of driving circuit 13
S2.Control unit 14 applies square to piezoelectric element 11 by turning on/off switch element Q1~Q4 of driving circuit 13 as a result,
The wavy driving voltage V1 of shape.
In the A of Fig. 3, as an example, the duty ratio shown in the first driving signal S1 and the second driving signal S2 is
The waveform of driving voltage V1 in the case where 50 (%).In the B of Fig. 3, as an example, show in the first driving signal S1 and
The duty ratio of second driving signal S2 be 40 (%) in the case where driving voltage V1 waveform.
In the present embodiment, the switching frequency of the frequency of driving voltage V1 and driving circuit 13 is and the first driving signal
The frequency of S1 and the second driving signal S2 are equal.In the following, by the frequency (driving of the first driving signal S1 and second of driving voltage V1
The frequency of signal S2) also referred to as " driving frequency ".In addition, in the present embodiment, " duty ratio of driving voltage V1 " refers to
(that is, driving voltage V1 is not during the interior driving voltage V1 to the application of piezoelectric element 11 of a cycle of driving voltage V1
During being zero) shared by ratio.The duty ratio of driving voltage V1 is equivalent to the first driving signal S1 and the second driving signal S2
2 times of duty ratio.That is, the duty ratio of the driving voltage V1 shown in the A of Fig. 3 is 50 × 2=100 (%),
The duty ratio of driving voltage V1 shown in the B of Fig. 3 is 40 × 2=80 (%).In the present embodiment, driving voltage V1's
It is 100 (%) (that is, the first driving signal S1 and second in the duty ratio of driving voltage V1 in fixed-size situation
The duty ratio of driving signal S2 is 50 (%)) when, the acoustic pressure for the sound that piezoelectric element 11 exports is maximum.
Temperature sensor 15 is thermistor, is installed on and is incorporated in the intracorporal substrate of shell.Liter is also installed in the substrate
Volt circuit 12, driving circuit 13 and control unit 14.Temperature sensor 15 by detection the intracorporal temperature of shell come directly or
Ground location places the temperature of the environment of piezoelectric element 11.The detection result of temperature sensor 15 is provided to control unit 14.
The mobile unit of the vehicle such as being used as being set to automobile of audio device 1 of present embodiment.In this case,
Audio device 1 is the alarm device in intrusion system, and is set on the wheel cover (wheel well: wheel cabin) of such as vehicle
Etc. the place being not readily visible.When detecting the intrusion of a suspect using the intrusion detection sensor being set in vehicle,
Audio device 1 generates for intimidateing effractor or for there are the alarm tones of effractor to surrounding notice.
(3) it acts
In the following, illustrating the movement of the audio device 1 of present embodiment using B, Fig. 4 of Fig. 1~Fig. 6 B.In this implementation
In mode, control unit 14 meet as defined in condition when, by with repeat include first period T1 and second phase T2 fixation
The mode of cycle T 0 controls driving voltage V1 export sound (being herein alarm tone) from piezoelectric element 11.In present embodiment
In, it is specified that condition refer to the intrusion that a suspect is detected using intrusion detection sensor.In addition, in the present embodiment,
Control unit 14 exports sound from piezoelectric element 11 during tens seconds from meeting defined condition.In addition, in this implementation
In mode, fixed cycle T0 includes an a first period T1 and second phase T2.That is, in the present embodiment,
Control unit 14 controls driving voltage V1 in a manner of alternately repeating first period T1 and second phase T2.
As shown in the B and Fig. 4 of Fig. 1, during each in first period T1 and second phase T2 of control unit 14, pass through
Driving frequency is set to be changed by T3 during every third to make driving frequency continuously change to second frequency from first frequency f11
f12.T3 is equivalent to a cycle of the first driving signal S1 and the second driving signal S2 during third, T3 during the third
Length changes according to driving frequency.That is, during third T3 length with driving frequency from first frequency f11 increase
It is added to second frequency f12 and shortens.Like this, control unit 14 is repeated the sound for exporting piezoelectric element 11 by T11 during every scanning
Sound continuously changes to the control of high pitch from bass.In the present embodiment, T11 is equivalent to first period T1 during scanning,
It is equivalent to second phase T2.In addition, in the present embodiment, first frequency f11 is, for example, 2.6 (kHz), second frequency f12
For example 3.4 (kHz).In addition, in the B of Fig. 1, it appears that seem that driving frequency is changed in T3 during third, but this
It is only indicated like this to indicate the consecutive variations of driving frequency, in fact, driving frequency in T3 during third
Rate is fixed.
As described above, in the present embodiment, the sound for exporting piezoelectric element 11 continuously changes to high pitch from bass,
This has the following advantages.For example, the sound that piezoelectric element 11 exports passes through in the case where audio device 1 is mobile unit
The car body etc. for constituting vehicle is output to the outside.Thus, in driving frequency and the resonance frequency by piezoelectric element 11 and vehicle defined
When rate is substantially uniform, the sound that piezoelectric element 11 exports most effectively is exported to the outside of vehicle.Resonant frequency is, for example, about 3
〔kHz〕。
Here, being set as since resonant frequency is different according to the type of vehicle in the sound for exporting piezoelectric element 11
Single-tone, that is to say, that it is different according to vehicle in the case where the sound for being set as fixed driving frequency, what piezoelectric element 11 exported
Sound is possible to be difficult to be output to the outside of vehicle.Therefore, in the present embodiment, by making driving frequency from than resonant frequency
Low first frequency continuously changes to second frequency, from regardless of the type of vehicle how, is all easy to keep piezoelectric element 11 defeated
Sound out is effectively output to the outside of vehicle.
In the present embodiment, control unit 14 based on be stored in memory, as shown in Table 1 below data control
Thus booster circuit 12 and driving circuit 13 control driving voltage V1." driving voltage " in table 1 indicates in second phase T2
Driving voltage V1, it is fixed that the driving voltage V1 in first period T1, which is 65 (V),.In addition, data shown in table 1 are one
Example, control unit 14 can also control driving voltage V1 based on the data different from data shown in table 1.
[table 1]
In first period T1, regardless of environment temperature, control unit 14 is driven with the first driving signal S1 and second
The mode that the duty ratio of signal S2 is 50 (%), the size of driving voltage V1 is 65 (V) controls booster circuit 12 and driving circuit
13.Therefore, in first period T1, no matter how environment temperature exports acoustic pressure (the first sound as benchmark to piezoelectric element 11
Pressure) sound.
In second phase T2, control unit 14 is according to environment temperature so that the first driving signal S1 and the second driving signal S2
The size changed mode of duty ratio and driving voltage V1 control booster circuit 12 and driving circuit 13.Therefore,
In second phase T2, piezoelectric element 11 exports the sound of second acoustic pressure lower than the first acoustic pressure according to environment temperature.
Specifically, control unit 14 reduces the second phase as the environment temperature detected by temperature sensor 15 increases
The second acoustic pressure in T2.Here, as shown in table 1, environment temperature is divided into multiple (being herein five) stages.
First stage is the stage in the case where environment temperature is -40 (DEG C)~40 (DEG C).In the first stage, control unit
14 in second phase T2 be 50 (%), driving voltage V1 with the duty ratio of the first driving signal S1 and the second driving signal S2
The mode that size is 65 (V) controls booster circuit 12 and driving circuit 13 (referring to Fig. 4).That is, in the first stage, control
Portion 14 has also carried out control identical with the control in first period T1 in second phase T2, therefore, in the first stage, second
The second acoustic pressure in period T2 is identical as the first acoustic pressure in first period T1.
Second stage is the stage in the case where environment temperature is 41 (DEG C)~50 (DEG C).In second stage, control unit
14 controls in such a way that the duty ratio of the first driving signal S1 and the second driving signal S2 are down to 40 (%) in second phase T2
Driving circuit 13 processed (referring to the A of Fig. 5).In addition, control unit 14 maintains the first rank in second phase T2 in second stage
The mode of the size of the driving voltage V1 of section controls booster circuit 12.Therefore, in second stage, compared with the first stage, second
Rising tone drops in period T2.Thus, in the rising tone pressure ratio first period T1 in second stage, the second phase
One acoustic pressure is low.
Phase III is the stage in the case where environment temperature is 51 (DEG C)~60 (DEG C).In the phase III, control unit
14 in second phase T2 with by the duty ratio of the first driving signal S1 and the second driving signal S2 be down to 30 (%) and will drive
The mode that the size of dynamic voltage V1 is down to 55 (V) controls booster circuit 12 and driving circuit 13 (referring to the B of Fig. 5).Therefore,
In three stages, the first acoustic pressure in rising tone pressure ratio first period T1 in second phase T2 is low, and compared with second stage, and
Rising tone pressure in two period T2 further reduces.
Fourth stage is the stage in the case where environment temperature is 61 (DEG C)~75 (DEG C).In fourth stage, control unit
14 controls in such a way that the duty ratio of the first driving signal S1 and the second driving signal S2 are down to 20 (%) in second phase T2
Driving circuit 13 processed (referring to the A of Fig. 6).In addition, control unit 14 maintains third rank in second phase T2 in fourth stage
The mode of the size of the driving voltage V1 of section controls booster circuit 12.Therefore, the rising tone in fourth stage, second phase T2
The first acoustic pressure in pressure ratio first period T1 is low, and compared with the phase III, and the rising tone pressure in second phase T2 is further
Ground reduces.
5th stage was the stage in the case where environment temperature is 76 (DEG C) or more.In fourth stage, control unit 14 exists
The duty ratio of the first driving signal S1 and the second driving signal S2 are down to 10 (%) and electricity will be driven in second phase T2
The mode that the size of pressure V1 is down to 40 (V) controls booster circuit 12 and driving circuit 13 (referring to the B of Fig. 6).Therefore, in the 5th rank
Section, the first acoustic pressure in rising tone pressure ratio first period T1 in second phase T2 is low, and compared with fourth stage, the second phase
Between rising tone pressure in T2 further reduce.
(4) advantage
As described above, in the present embodiment, piezoelectric element 11 is in the first period T1 in fixed cycle T0, output the
The sound of one acoustic pressure exports the sound of second acoustic pressure lower than the first acoustic pressure according to environment temperature in second phase T2.Cause
And in the present embodiment, it has the advantage that and for example persistently exports what piezoelectric element 11 can export with piezoelectric element 11
The case where sound of maximum acoustic pressure, is compared, and the rising of environment temperature is able to suppress, from the results of view the piezoelectricity in audio device 1
The sound that element 11 exports is not easy to reduce.
In the following, specifically describing the advantage.Environment temperature is mainly by piezoelectric element 11 and the fever of driving circuit 13
It rises.Moreover, the temperature of piezoelectric element 11 also exceedingly rises in the state that environment temperature exceedingly rises, it is possible to due to
The difference etc. of thermal expansion coefficient causes to crack in piezoelectric board (being herein the first piezoelectric board 111 and the second piezoelectric board 112).It is false
In the case where such as producing crackle in piezoelectric board, the sound that piezoelectric element 11 exports is possible to reduce.
Here, piezoelectric element 11 is mainly generated heat by mechanically vibrating.Moreover, the vibration of piezoelectric element 11 is bigger, then
More export the sound of high sound pressure.That is, piezoelectric element 11 export sound the more high then described piezoelectric element 11 of acoustic pressure more
Fever.
In addition, driving circuit 13 is mainly generated heat by electric current flowing.Moreover, the acoustic pressure for the sound that piezoelectric element 11 exports
More Gao Ze has bigger electric current to flow through in driving circuit 13.That is, the acoustic pressure for the sound that piezoelectric element 11 exports is higher
Then driving circuit 13 more generates heat.
Moreover, as present embodiment, in the case where piezoelectric element 11 and driving circuit 13 are incorporated in shell,
The heat that piezoelectric element 11 and driving circuit 13 generate is easily accumulated in shell.Therefore, environment temperature is with 11 He of piezoelectric element
The increase of the calorific value of driving circuit 13 and rise.Thus, in order to avoid rising to environment temperature exceedingly in piezoelectric board
The degree cracked needs to be controlled such that the calorific value of piezoelectric element 11 and driving circuit 13 will not exceedingly increase.
Therefore, in the present embodiment, the side of the fixed cycle T0 with repetition including first period T1 and second phase T2
Formula controls driving voltage V1, first acoustic pressure of the output as benchmark in the first period T1, in the second phase T2
Export the second acoustic pressure corresponding with environment temperature lower than the first acoustic pressure.Therefore, in the present embodiment, peak value sound can not be made
Pressure (the first acoustic pressure) damply (that is, ensure in fixed cycle T0 export the first acoustic pressure sound during), suppression
The calorific value of piezoelectric element 11 and driving circuit 13 processed, to inhibit the rising of environment temperature.
(5) variation
Above-mentioned embodiment is one of various embodiments of the disclosure.As long as above-mentioned embodiment can be realized
The purpose of the disclosure can then make various changes according to design etc..For example, audio device 1 is also possible to only have control unit
14 sound controller 100 (A referring to Fig.1).That is, sound controller 100 involved in a mode controls
It is applied to the driving voltage V1 of piezoelectric element 11, which receives periodic driving voltage V1 and vibrates, from
And export the sound of acoustic pressure corresponding with driving voltage V1.Sound controller 100 has to repeat include first period T1 with
The mode of the fixed cycle T0 of second phase T2 controls the function of driving voltage V1.First period T1 is to export piezoelectric element 11
During sound as the first acoustic pressure of benchmark.Second phase T2 makes piezoelectric element 11 according to being placed with piezoelectric element 11
During sound of the temperature of environment to export the second acoustic pressure lower than the first acoustic pressure.
Alternatively, it is also possible to have non-transitory recording medium of computer program etc. come real by computer program or record
Now function identical with control unit 14.That is, program involved in a mode is to be applied to piezoelectric element for controlling
The program of 11 driving voltage V1, the piezoelectric element 11 receive periodic driving voltage V1 and vibrate, thus output with
The sound of the corresponding acoustic pressure of driving voltage V1.Program makes computer system execute following processing: including first period T1 to repeat
Driving voltage V1 is controlled with the mode of the fixed cycle T0 of second phase T2.First period T1 is that piezoelectric element 11 is made to export conduct
During the sound of first acoustic pressure of benchmark.Second phase T2 is to make piezoelectric element 11 according to the environment for being placed with piezoelectric element 11
Sound of the temperature to export second acoustic pressure lower than the first acoustic pressure during.
In the following, enumerating the variation of above-mentioned embodiment.Variation described below can be appropriately combined to apply.
The control unit 14 of audio device 1 in the disclosure includes computer system.Computer system is using the place as hardware
It manages device and memory is main structure.Made by executing the program being recorded in the memory of computer system by processor to realize
For the function of the control unit 14 in the disclosure.Program can be both previously recorded in the memory of computer system, can also be led to
Electrical communication line is crossed to provide, storage card, the CD, hard drive that can be read using computer system can also be recorded in
It is provided in the non-transitories recording medium such as device.The processor of computer system by include semiconductor integrated circuit (IC) or
One of large scale integrated circuit (LSI) is constituted to multiple electronic circuits.Multiple electronic circuits both can integrate in a chip,
Multiple chips can also be dispersedly set to.Multiple chips both can integrate in a device, can also dispersedly be set to more
A device.
In the above-described embodiment, piezoelectric element 11 is not limited to the piezoelectric element of bimorph type, can also be with
It is the pressure of unimorph (Unimorph) type that a piece of piezoelectric board is arranged in a face on the thickness direction of a piece of oscillating plate
Electric device.In this case, as long as control unit 14 is with flowering structure: only by the first driving signal S1 and the second driving signal
The driving signal of one party in S2 is provided in such a way that duty ratio is set as twice to driving circuit 13.
In the above-described embodiment, control unit 14 is by driving the first driving signal S1 and second according to environment temperature
The duty ratio of signal S2 and the size of driving voltage V1 change to make the second sound pressure variations in second phase T2, still
Objective is not limited to this.For example, control unit 14 can not also make driving voltage V1 change and make the according only to environment temperature
Thus the change in duty cycle of one driving signal S1 and the second driving signal S2 make the second sound pressure variations in second phase T2.Separately
Outside, control unit 14 can not also make the change in duty cycle of the first driving signal S1 and the second driving signal S2 and according only to environment temperature
The size variation to make driving voltage V1 is spent, the second sound pressure variations in second phase T2 are thus made.
In the above-described embodiment, it during each in first period T1 and second phase T2 of control unit 14, presses
Every 3rd period T3 changes driving frequency.Moreover, in the above-described embodiment, as shown in fig. 7, control unit 14 can also be with
T3 synchronously makes sound pressure variations during third.
In the example shown in Fig. 7, during each in first period T1 and second phase T2, the of first time
The duty ratio of the first driving signal S1 and the second driving signal S2 are 50 (%) in three period T3.On the other hand, secondary
The duty ratio of the first driving signal S1 and the second driving signal S2 are 20 (%) in T3 during third.Control unit 14 is like this
During each in one period T1 and second phase T2, in a manner of the T3 during alternately to repeat the mutually different third of acoustic pressure
Control driving voltage V1.That is, here, control unit 14 makes sound press change by T3 during every third.Certainly, it controls
Portion 14 can also make sound press change by T3 during every multiple thirds.
In addition, in the above-described embodiment, control unit 14 can also be by making in fixed cycle T0 according to environment temperature
First period T1 and the ratio (hereinafter, also referred to as " ratio ") of second phase T2 change to make in second phase T2
Second sound pressure variations.For example, control unit 14 can also increase the second phase in fixed cycle T0 as environment temperature increases
Ratio shared by T2.In this case, control unit 14 can not only make ratio be changed according to environment temperature, can also make
The size of the duty ratio and driving voltage V1 of one driving signal S1 and the second driving signal S2 also becomes according to environment temperature
Change.That is, control unit 14 can also be by making the first driving signal S1 and the second driving signal S2 according to environment temperature
At least one of duty ratio, the size of driving voltage V1 and ratio change to make the rising tone in second phase T2
Buckling.
In the above-described embodiment, during each in first period T1 and second phase T2 of control unit 14, make
Driving frequency continuously changes to second frequency f12 from first frequency f11, but objective is not limited to this.For example, control
Portion 14 can also make to drive during each in first period T1 and second phase T2 by making during third T3 longer
Frequency discretely changes to second frequency f12 from first frequency f11.
In addition, in the above-described embodiment, control unit 14 can also be each in first period T1 and second phase T2
During a, driving voltage V1 is controlled in a manner of becoming fixed driving frequency.That is, control unit 14 can also with so that
The mode that the sound that piezoelectric element 11 exports is set as single-tone controls driving voltage V1.
In the above-described embodiment, audio device 1 has temperature sensor 15, but objective is not limited to this.
That is, audio device 1 can both be built-in with temperature sensor 15, it is also possible to receive detection from the temperature sensor of peripheral hardware
The structure of signal.In the case where being the latter, as long as control unit 14 is using the detection temperature of the temperature sensor of peripheral hardware as environment
Temperature controls driving voltage V1.
In the above-described embodiment, audio device 1 has booster circuit 12, but objective is not limited to this.Example
Such as, voltage required for for driving piezoelectric element 11 can be being directly fed to driving circuit 13 and is being carried out only by the
The duty ratio of one driving signal S1 and the second driving signal S2 make the rising tone in second phase T2 press changed control
In the case where, do not need booster circuit 12.
In the above-described embodiment, driving circuit 13 is the inverter of bridge-type, but objective is not limited to this.
For example, as described above, driving circuit 13 may not be entirely if piezoelectric element 11 is the piezoelectric element of unimorph type
The inverter of bridge type.
In the above-described embodiment, driving circuit 13 is incorporated in the shell of audio device 1, but objective is not
It is defined in this.For example, driving circuit 13 can also be configured at outside shell.In this case, due to the heat of the generation of driving circuit 13
It is difficult to be transmitted in shell, therefore is able to suppress the rising of environment temperature.In addition, about the miniaturization side for realizing audio device 1
Face, it is ideal that driving circuit 13, which is configured in shell,.
In the above-described embodiment, audio device 1 is set in vehicle, but objective is not limited to this.It is preferred that
Be that audio device 1 is set to that equal such as the high place of air-tightness, to be placed with the temperature of the environment of audio device 1 easy because to sound
Ring the environment that device 1 is driven up.
In the above-described embodiment, audio device 1 is used as motor vehicle alarm device, but objective is not limited to
This.For example, audio device 1 is in addition to being used as electric car, magnetic suspension train, independent ambulation robot etc. in the moving body of land walking
Alarm device outside, be also used as the alarm device of the moving body than vehicles such as the flying bodies such as unmanned plane, aircraft or ship.
(summary)
As described above, audio device involved in first method (1) has piezoelectric element (11) and control unit (14).Piezoelectricity
Element (11) receives periodic driving voltage (V1) and vibrates, thus output acoustic pressure corresponding with driving voltage (V1)
Sound.Control unit (14) controls driving voltage (V1).Control unit (14) includes first period (T1) and the second phase to repeat
(T2) mode of fixed cycle (T0) controls driving voltage (V1).First period (T1) is that piezoelectric element (11) is made to export conduct
During the sound of first acoustic pressure of benchmark.The second phase (T2) is that piezoelectric element (11) basis is made to be placed with piezoelectric element (11)
Environment sound of the temperature to export second acoustic pressure lower than the first acoustic pressure during.
According to which, the acoustic pressure for the sound that the piezoelectric element (11) in audio device (1) issues is had the advantage that not
Easily reduce.
The audio device involved in second method (1), in first method, control unit (14) change driving voltage
(V1) duty ratio makes the second sound pressure variations.
According to which, have the advantage that by keeping the change in duty cycle of driving voltage (V1) this simple
Control is to make the second sound pressure variations.
The audio device involved in Third Way (1), in first method or second method, control unit (14) changes
The size of driving voltage (V1) makes the second sound pressure variations.
According to which, this simple control of size variation by making driving voltage (V1) is had the advantage that
System is to make the second sound pressure variations.
The audio device involved in fourth way (1), in any one mode in first method~Third Way,
During each in first period (T1) and the second phase (T2) of control unit (14), change drive by (T3) during every third
The frequency (driving frequency) of dynamic voltage (V1), and synchronously make sound pressure variations with T3 during third.
According to which, has the advantage that and match with the variation of the pitch of the sound of piezoelectric element (11) output
Close the sound pressure variations for the sound that ground exports piezoelectric element (11).
The audio device (1) involved in the 5th mode, in fourth way, during control unit (14) presses every third
(T3) make sound pressure variations.
According to which, have the advantage that according to piezoelectric element (11) output sound pitch variation come
The sound pressure variations for the sound for exporting piezoelectric element (11).
The audio device (1) involved in the 6th mode, in any one mode in first method~the 5th mode,
Control unit (14) changes the first period (T1) in fixed cycle (T0) and the ratio of the second phase (T2) according to environment temperature.
According to which, having the advantage that does not make rising tone drops and is easy to inhibit the rising of environment temperature.
The audio device (1) involved in the 7th mode, in any one mode in first method~the 6th mode,
Environment temperature is divided into multiple stages.Control unit (14) keeps rising tone pressure drop low as environment temperature increases.
According to which, have the advantage that and the feelings that reduce the second acoustic pressure continuously
Condition is compared, and driving voltage (V1) is easy to control.
Sound controller involved in eighth mode (100) controls the driving voltage for being applied to piezoelectric element (11)
(V1), which receives periodic driving voltage (V1) and vibrates, thus output and driving voltage (V1)
The sound of corresponding acoustic pressure.Sound controller (100) has to repeat to include first period (T1) and the second phase (T2)
The mode of fixed cycle (T0) controls the function of driving voltage (V1).First period (T1) is that piezoelectric element (11) is made to export conduct
During the sound of first acoustic pressure of benchmark.The second phase (T2) is that piezoelectric element (11) basis is made to be placed with piezoelectric element (11)
Environment sound of the temperature to export second acoustic pressure lower than the first acoustic pressure during.
According to which, having the advantage that makes to be placed with the piezoelectric element controlled by sound controller (100)
(11) temperature of environment rises, and the acoustic pressure for the sound that piezoelectric element (11) issues also is not easy to reduce.
Program involved in 9th mode is the program for controlling the driving voltage (V1) for being applied to piezoelectric element (11),
The piezoelectric element (11) receives periodic driving voltage (V1) and vibrates, so that output is corresponding with driving voltage (V1)
The sound of acoustic pressure.Program makes computer system execute following processing: including first period (T1) and the second phase (T2) to repeat
The mode of fixed cycle (T0) control driving voltage (V1).First period (T1) is to make piezoelectric element (11) output as benchmark
The first acoustic pressure sound during.The second phase (T2) is to make piezoelectric element (11) according to the ring for being placed with piezoelectric element (11)
During sound of the temperature in border to export the second acoustic pressure lower than the first acoustic pressure.
According to which, the temperature for making to be placed with the environment by the piezoelectric element (11) of process control is had the advantage that
Degree rises, and the acoustic pressure for the sound that piezoelectric element (11) issues also is not easy to reduce.
Structure involved in second method~the 7th mode is not structure necessary to audio device (1), can suitably be saved
Slightly.
Description of symbols
1: audio device；11: piezoelectric element；14: control unit；15: temperature sensor；100: sound controller；T0: Gu
Fixed cycle；T1: first period；T2: the second phase；T3: during third；V1: driving voltage.
Claims (9)
1. a kind of audio device, which is characterized in that have:
Piezoelectric element receives periodic driving voltage and vibrates, thus output sound corresponding with the driving voltage
The sound of pressure；And
Control unit controls the driving voltage,
Wherein, the control unit controls the driving electricity in a manner of the fixed cycle for repeating to include first period and the second phase
Pressure,
The first period is during making sound of the piezoelectric element output as the first acoustic pressure of benchmark,
The second phase is to make the piezoelectric element and exported according to the temperature for the environment for being placed with the piezoelectric element to compare institute
During the sound for stating the second low acoustic pressure of the first acoustic pressure.
2. audio device according to claim 1, which is characterized in that
The control unit changes the duty ratio of the driving voltage to make second sound pressure variations.
3. audio device according to claim 1 or 2, which is characterized in that
The control unit changes the size of the driving voltage to make second sound pressure variations.
4. audio device described according to claim 1~any one of 3, which is characterized in that
During each in the first period and the second phase of the control unit, by during every third to change
State the frequency of driving voltage, and with synchronously make the sound pressure variations during the third.
5. audio device according to claim 4, which is characterized in that
The control unit makes the sound pressure variations by during every third.
6. audio device described according to claim 1~any one of 5, which is characterized in that
The control unit changes the first period and described second in the fixed cycle according to the temperature of the environment
The ratio of period.
7. audio device described according to claim 1~any one of 6, which is characterized in that
The temperature of the environment is divided into multiple stages, and the control unit makes described second as the temperature of the environment increases
Acoustic pressure reduces.
8. a kind of sound controller, control is applied to the driving voltage of piezoelectric element, and the piezoelectric element receives periodic
Driving voltage and vibrate, thus the sound of corresponding with the driving voltage acoustic pressure of output,
The sound controller has controls the drive in a manner of the fixed cycle for repeating to include first period and the second phase
The function of dynamic voltage,
The first period is during making sound of the piezoelectric element output as the first acoustic pressure of benchmark,
The second phase is to make the piezoelectric element and exported according to the temperature for the environment for being placed with the piezoelectric element to compare institute
During the sound for stating the second low acoustic pressure of the first acoustic pressure.
9. a kind of program, for controlling the driving voltage for being applied to piezoelectric element, the piezoelectric element receives periodically driving
Voltage and vibrate, thus the sound of corresponding with the driving voltage acoustic pressure of output,
Described program makes computer system execute following processing: to repeat the fixed cycle including first period and the second phase
Mode controls the driving voltage,
The first period is during making sound of the piezoelectric element output as the first acoustic pressure of benchmark,
The second phase is to make the piezoelectric element and exported according to the temperature for the environment for being placed with the piezoelectric element to compare institute
During the sound for stating the second low acoustic pressure of the first acoustic pressure.
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2017252582A JP6872723B2 (en) | 2017-12-27 | 2017-12-27 | Acoustic devices, acoustic control devices, and programs |
| JP2017-252582 | 2017-12-27 | ||
| PCT/JP2018/047587 WO2019131639A1 (en) | 2017-12-27 | 2018-12-25 | Acoustic device, acoustic control device, and program |
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| CN110199345A true CN110199345A (en) | 2019-09-03 |
| CN110199345B CN110199345B (en) | 2023-08-01 |
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| CN201880005537.3A Active CN110199345B (en) | 2017-12-27 | 2018-12-25 | Sound device, sound control device, and recording medium |
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|---|---|
| JP (1) | JP6872723B2 (en) |
| CN (1) | CN110199345B (en) |
| DE (1) | DE112018004165T5 (en) |
| WO (1) | WO2019131639A1 (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111710323A (en) * | 2020-05-19 | 2020-09-25 | 深圳南云微电子有限公司 | Buzzer control method and control circuit thereof |
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| WO2023032524A1 (en) * | 2021-09-06 | 2023-03-09 | ローム株式会社 | Sound wave processing device, and ultrasonic system |
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| CN102959990A (en) * | 2010-08-26 | 2013-03-06 | 株式会社村田制作所 | Piezoelectric device |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH11153994A (en) | 1997-11-19 | 1999-06-08 | Matsushita Electric Ind Co Ltd | Ringing device |
-
2017
- 2017-12-27 JP JP2017252582A patent/JP6872723B2/en active Active
-
2018
- 2018-12-25 WO PCT/JP2018/047587 patent/WO2019131639A1/en active Application Filing
- 2018-12-25 CN CN201880005537.3A patent/CN110199345B/en active Active
- 2018-12-25 DE DE112018004165.4T patent/DE112018004165T5/en active Pending
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|---|---|---|---|---|
| JPH09147269A (en) * | 1995-11-20 | 1997-06-06 | Hochiki Corp | Alarm sound device |
| JPH09301060A (en) * | 1996-05-13 | 1997-11-25 | Niles Parts Co Ltd | Electronic flasher device |
| CN1535187A (en) * | 2001-07-25 | 2004-10-06 | ����-��ϣ�ɷݹ�˾ | Signal born with adaptively modifiable operating variables |
| JP2009101895A (en) * | 2007-10-24 | 2009-05-14 | Mitsubishi Electric Corp | On-vehicle buzzer sound pressure control device |
| CN102959990A (en) * | 2010-08-26 | 2013-03-06 | 株式会社村田制作所 | Piezoelectric device |
| CN104412321A (en) * | 2012-06-25 | 2015-03-11 | 松下知识产权经营株式会社 | Alarm drive circuit |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111710323A (en) * | 2020-05-19 | 2020-09-25 | 深圳南云微电子有限公司 | Buzzer control method and control circuit thereof |
| CN111710323B (en) * | 2020-05-19 | 2023-07-11 | 深圳南云微电子有限公司 | Buzzer control method and control circuit thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2019117360A (en) | 2019-07-18 |
| JP6872723B2 (en) | 2021-05-19 |
| CN110199345B (en) | 2023-08-01 |
| WO2019131639A1 (en) | 2019-07-04 |
| DE112018004165T5 (en) | 2020-04-30 |
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