TW201424888A - A vibration processing apparatus and a vibration driving module thereof - Google Patents

Abstract

A vibration processing apparatus comprises a piezoelectric actuator and a vibration driving module. The piezoelectric actuator receives a driving voltage and generates a driving current which changes its amplitude with a frequency of the driving voltage. The vibration driving module used to generate the driving voltage, and includes a current sensor and an analysis control unit. The current sensor used to sense a plurality of different frequencies of the driving current, and generates a sensing value based on the size of each of the driving current. The analysis control unit received and stored each sensing value and the frequency corresponding to each of the sensing values, and sets the maximum one of such sensing value stored corresponding to the frequency for a operating frequency of the driving voltage, so that the piezoelectric actuator vibrates at a resonant frequency.

Description

Vibration processing device and vibration driving module thereof

The invention relates to a processing device and a driving module thereof, in particular to a vibration processing device for generating ultrasonic vibration and a vibration driving module thereof.

Referring to FIG. 1, a conventional ultrasonic vibration processing apparatus 1 includes a processing machine 11, a vibration table 12, and a vibration driving module 13.

When the processing machine 11 is used to machine a workpiece 2 to be placed on the vibrating table 12, for example, when performing rotary cutting, the vibration of the vibrating table 12 helps to extend the tool life of the processing machine 11 and Help with chip removal.

The vibrating table 12 includes a piezoelectric actuator 121. The piezoelectric actuator 121 generates vibration by using an AC voltage received, and a vibration frequency of the piezoelectric actuator 121 is a frequency positively correlated with the AC voltage, and when the piezoelectric actuator 121 vibrates At the time, portions of the vibrating table 12 other than a fixed base vibrate together.

When the processing machine 11 is used to machine a workpiece 2 to be placed on the vibrating table 12, such as rotary cutting, the vibration of the vibrating table 12 helps to extend the tool life and help of the processing machine 11. Chip removal.

The vibration driving module 13 includes a power meter 131 and an analysis control unit 132.

The power meter 131 is fixed to the vibrating table 12 to sense the vibration of the vibrating table 12 and output a vibration signal.

The analysis control unit 132 is electrically connected to the piezoelectric actuator 121 to provide The AC voltage is electrically connected to the power meter 131 to receive the vibration signal, and the vibration frequency of the piezoelectric actuator 121 is determined according to the vibration signal, and the frequency of the AC voltage is adjusted according to the determined vibration frequency, with a view to The frequency of the alternating voltage is operated at a resonant frequency of the piezoelectric actuator 121, wherein the piezoelectric actuator 121 operates at the resonant frequency with a maximum mechanical amplitude.

The disadvantages of this type of supersonic vibration processing device 1 are:

When the processing machine 11 is restrained by the workpiece 2, the vibration frequency of the vibration table 12 deviates from the vibration frequency of the piezoelectric actuator 121. However, the power meter 131 does not directly measure the vibration frequency. The vibration of the piezoelectric actuator 121 is the vibration of the vibrating table 12, which causes the analysis control unit 132 to fail to adjust the frequency of the alternating voltage according to the vibration signal to be equal to the resonant frequency of the piezoelectric actuator 121. This causes the piezoelectric actuator 121 to fail to reach the maximum mechanical amplitude.

Accordingly, it is an object of the present invention to provide a vibration processing apparatus that can solve the disadvantages of the prior art.

Therefore, the vibration processing apparatus of the present invention comprises a piezoelectric actuator and a vibration driving module.

The piezoelectric actuator receives a driving voltage and generates vibration according to a frequency of the driving voltage, and generates a driving current whose magnitude varies with a frequency of the driving voltage.

The vibration driving module is electrically connected to the piezoelectric actuator and generates the driving voltage, and includes a current sensor and an analysis control unit.

The current sensor is configured to sense a magnitude of the driving current corresponding to the plurality of different frequencies, and output a sensing value according to the sensed magnitude of each driving current.

The analysis control unit is electrically connected to the current sensor to receive each sensed value, and stores each sensed value and the frequency corresponding to each sensed value, and the analysis control unit stores the sensed The frequency corresponding to the largest one of the measured values is set to an operating frequency of the driving voltage to cause the piezoelectric actuator to vibrate at a resonant frequency.

Another object of the present invention is to provide a vibration driving module suitable for use in a vibration processing apparatus, the vibration processing apparatus comprising a piezoelectric actuator, the piezoelectric actuator receiving a driving voltage, and according to the The frequency of the driving voltage generates vibration, and the piezoelectric actuator generates a driving current whose magnitude varies with a frequency of the driving voltage.

The vibration driving module is electrically connected to the piezoelectric actuator and generates the driving voltage, and includes a current sensor and an analysis control unit.

The current sensor is configured to sense a magnitude of the driving current corresponding to the plurality of different frequencies, and output a sensing value according to the sensed magnitude of each driving current.

The analysis control unit is electrically connected to the current sensor to receive each sensed value, and stores each sensed value and the frequency corresponding to each sensed value, and the analysis control unit stores the sensed The frequency corresponding to the largest one of the measured values is set to an operating frequency of the driving voltage to cause the piezoelectric actuator to vibrate at a resonant frequency.

Yet another object of the present invention is to provide a frequency modulation method suitable for For performing by a vibration driving module, the vibration driving module is configured to generate a driving voltage to be supplied to a piezoelectric actuator, so that the piezoelectric actuator generates vibration according to a frequency of the driving voltage, and the frequency modulation method includes : (A) sensing a magnitude of the driving current corresponding to the plurality of different frequencies, and outputting a sensing value according to the sensed magnitude of each driving current; and (B) storing each sensing value, And the frequency corresponding to each sensed value, and the analysis control unit sets the frequency corresponding to the largest one of the stored sensing values as an operating frequency of the driving voltage.

The above and other technical contents, features and advantages of the present invention will be apparent from the following detailed description of the preferred embodiments.

Referring to FIG. 2, a preferred embodiment of the vibration processing apparatus of the present invention comprises a piezoelectric actuator 3 and a vibration drive module 4.

The piezoelectric actuator 3 is preferably disposed on a tool 5, but is not limited thereto, and may be disposed on a working machine (not shown). The piezoelectric actuator 3 receives a driving voltage, generates vibration according to the frequency of the driving voltage, and generates a driving current whose magnitude varies with a frequency of the driving voltage.

The cutter 5 is interlocked when the piezoelectric actuator 3 vibrates, and when the frequency of the driving voltage is substantially equal to a resonant frequency of the piezoelectric actuator 3, the piezoelectric actuator 3 The maximum mechanical amplitude is generated, which in turn drives the tool 5 to produce maximum mechanical amplitude for optimum machining results.

Usually, the piezoelectric actuator 3 is first measured by an impedance analyzer. A plot of impedance versus frequency as shown in FIG. 3, and a frequency corresponding to the valley of the curve is an original resonant frequency at which the piezoelectric actuator 3 is shipped, but as time increases or is actually used The external force of the tool 5 is restrained, and a current resonant frequency of the piezoelectric actuator 3 deviates from the original resonant frequency, and the preferred embodiment can not only avoid the problems of the prior art, but also perform a frequency modulation method. The resonant frequency of the piezoelectric actuator 3 at each use is known, which in turn causes the piezoelectric actuator 3 to resonate to achieve maximum mechanical amplitude using the current resonant frequency.

The vibration driving module 4 is electrically connected to the piezoelectric actuator 3 and generates the driving voltage, and includes a current sensor 41, an analysis control unit 42, and a phase difference detector 43.

As shown in FIG. 4 and FIG. 5, the vibration driving module 4 performs a frequency modulation method, and the frequency modulation method includes a scanning mode and a resonance mode, and the scanning mode includes the following steps:

Step 51: The frequency of the driving voltage is sequentially set to a plurality of different frequencies by the analysis control unit 42.

Explain in detail that the selection of the frequencies of the driving voltage is started as shown in FIG. 4 with the original resonant frequency when the piezoelectric actuator 3 is shipped, and then the difference is added and subtracted.

By way of example and not limitation, if the original resonant frequency is 40.1 kHz and the sampling is equally spaced at 0.1 kHz, the samples are generated by the frequency f(i)=40.1±(0.1×i) kHz, where i =0, 1, 2, 3...

Step 52: The current sensor 41 is used to sense the magnitude of the driving current corresponding to the plurality of different frequencies, and according to each sensed driving power The magnitude of the stream outputs a sensed value, and the magnitude of the sensed value is changed synchronously following the magnitude of the drive current.

In the preferred embodiment, the current sensor 41 is a Hall current sensor, the sensing value is a voltage, and the sense is greater when the current sensed by the current sensor 41 is greater. The measured value (voltage) is also higher.

Step 53: The analysis control unit 42 is electrically connected to the current sensor 41, and receives each sensed value output by the current sensor 41, and stores each sensed value and each sensed value corresponding to each The frequency.

Step 54: Using the analysis control unit 42 to determine why the largest one of the stored sensing values is stored.

Step 55: Determine the frequency of the maximum corresponding to the sensed value. As exemplified in Fig. 4, the maximum sensed value is 1.2 amps, and the resonant frequency of the piezoelectric actuator 3 is 39.9 kHz.

It should be noted that the frequency of the driving voltage does not necessarily need to be set according to the sequence of steps selected in step 51, and different frequencies may also be pre-stored in the analysis control unit 42 or input in the file type. It is stored in the analysis control unit 42 or calculated by the analysis control unit 42 with an input set scan resolution and a scan frequency band, and a center frequency of the scan frequency band is the original resonance frequency.

The resonant mode includes the following steps:

Step 56: The frequency of the driving voltage is set to the operating frequency by the analysis control unit 42.

Referring to FIG. 6, the frequency modulation method further includes a phase lock mode, and the phase lock mode and the scan mode can be performed in a time division manner, or can be simultaneously parallel. The pattern contains the following steps 61 through 64:

Step 61: The phase difference detector 43 is electrically connected to the analysis control unit 42 to receive the driving voltage, and electrically connected to the current sensor 41 to receive the sensing value, and output an indication of the driving voltage and the sensing. A phase comparison signal of a phase difference between values. In the preferred embodiment, the phase difference detector 43 is implemented by a Texas Instruments model CD4046 chip, but is not limited thereto.

Step 62: The phase comparison signal is received by the analysis control unit 42.

Step 63: The analysis control unit 42 determines whether the phase difference is substantially zero according to the phase comparison signal, and if so, ends, if not, proceeds to step 64.

Step 64: The analysis control unit 42 adjusts a voltage phase of the driving voltage according to the phase comparison signal, and returns to step 62.

By the foregoing steps 62 to 64, when the phase difference is substantially not zero, the analysis control unit 42 continuously adjusts the voltage phase of the driving voltage until the phase difference is substantially zero, and then stops adjusting. The voltage phase of the drive voltage.

When the phase difference is substantially zero, the driving voltage is substantially in phase with the sensing value, and since the sensing value substantially changes in accordance with the magnitude of the driving current, the sensing value can be regarded as The driving current is in phase, that is, the driving voltage is in phase with the driving current, which causes a driving power received by the piezoelectric actuator 3 to have a maximum power factor (PF), thereby causing the piezoelectric actuation 3 and the vibration driving module 4 The maximum electromechanical conversion efficiency is achieved to save energy, and the piezoelectric actuator 3 can also be brought to a greater mechanical amplitude, wherein the voltage of the driving power is the driving voltage, and the current of the driving power is the driving current. .

In more detail, the analysis control unit 42 has a controller 421, a voltage controlled oscillator 422, a power amplifier 423, and an impedance matcher 424.

The controller 421 is configured to output a control signal, and electrically connect the current sensor 41 to receive each sensed value output by the current sensor 41, store each sensed value and the corresponding frequency thereof, and determine The largest one of the stored sensing values, and the frequency corresponding to the largest determined sensing value is used as the frequency of the control signal.

The voltage controlled oscillator 422 is electrically connected to the controller 421 to receive the control signal, and is controlled by the control signal to output an oscillating signal, and the frequency of the oscillating signal is controlled by the frequency of the control signal. In an embodiment, the frequency of the oscillation signal is equal to the frequency of the control signal.

The power amplifier 423 is electrically connected to the voltage controlled oscillator 422 to receive the oscillating signal, and amplifies the amplitude of the oscillating signal into an enhanced oscillating signal and outputs the frequency of the oscillating signal equal to the frequency of the oscillating signal.

The impedance matching unit 424 is electrically connected to the power amplifier 423 to receive the enhanced oscillation signal, and converts the enhanced oscillation signal into the driving voltage and outputs the frequency of the driving voltage equal to the frequency of the enhanced oscillation signal. In short, the controller 421 can control the frequency and phase of the driving voltage by controlling the frequency and phase of the control signal. The aforementioned frequency modulation method is performed.

In summary, the preferred embodiment has the following advantages:

1. The vibration driving module 4 performs the frequency modulation method to determine the resonant frequency of the piezoelectric actuator 3 by using the sensing value, thereby avoiding the prior art misjudge the resonant frequency due to mechanical errors when the power meter 131 measures. .

2. The vibration driving module 4 performs the frequency sweeping method to obtain the resonant frequency of the piezoelectric actuator 3, so that the frequency of the driving voltage is surely operated at the resonant frequency of the piezoelectric actuator 3. .

3. The phase-locking mode step of the frequency sweeping method can adjust the phase of the driving voltage so that the driving voltage and the driving current remain substantially in phase, and the vibration driving module 4 and the piezoelectric actuator 3 can be further Maximum electromechanical conversion efficiency is achieved between.

In summary, the above preferred embodiments can achieve the object of the present invention.

The above is only the preferred embodiment of the present invention, and the scope of the invention is not limited thereto, that is, the simple equivalent changes and modifications made by the scope of the invention and the description of the invention are All remain within the scope of the invention patent.

1‧‧‧Supersonic vibration processing device

11‧‧‧Processing machine

12‧‧‧Vibration table

121‧‧‧ Piezoelectric Actuator

13‧‧‧Vibration drive module

131‧‧‧Power Meter

132‧‧‧Analytical Control Unit

2‧‧‧To be processed

3‧‧‧ Piezoelectric actuator

4‧‧‧Vibration drive module

41‧‧‧ Current Sensor

42‧‧‧Analytical Control Unit

421‧‧‧ Controller

422‧‧‧Variable Control Oscillator

423‧‧‧Power Amplifier

424‧‧‧impedance matcher

43‧‧‧ phase difference detector

5‧‧‧Tools

51~56‧‧‧Steps

61~64‧‧‧Steps

1 is a schematic view of a conventional ultrasonic vibration processing apparatus; FIG. 2 is a block diagram of a preferred embodiment of the vibration processing apparatus of the present invention; and FIG. 3 is a schematic diagram showing the impedance of a piezoelectric actuator with frequency Change relationship 4 is a diagram illustrating a variation of a sensed value versus a frequency of a driving voltage in the preferred embodiment; FIG. 5 is a flow chart illustrating a frequency modulation method performed by the preferred embodiment including a scan mode And a resonant mode; and FIG. 6 is a flow chart illustrating that the frequency modulation method performed by the preferred embodiment further includes a phase lock mode.

3‧‧‧ Piezoelectric actuator

4‧‧‧Vibration drive module

41‧‧‧ Current Sensor

42‧‧‧Analytical Control Unit

421‧‧‧ Controller

422‧‧‧Variable Control Oscillator

423‧‧‧Power Amplifier

424‧‧‧impedance matcher

43‧‧‧ phase difference detector

5‧‧‧Tools

Claims (10)

A vibration processing apparatus comprising: a piezoelectric actuator that receives a driving voltage, generates vibration according to a frequency of the driving voltage, and generates a driving current of a magnitude varying with a frequency of the driving voltage; and a vibration driving mode The group is electrically connected to the piezoelectric actuator and generates the driving voltage, and includes: a current sensor for sensing a magnitude of the driving current corresponding to the plurality of different frequencies, and sensing according to the sensing And a magnitude of each driving current to output a sensing value; and an analysis control unit electrically connected to the current sensor to receive each sensing value, and store each sensing value, and each sensing value Corresponding to the frequency, and the analysis control unit sets the frequency corresponding to the largest one of the stored sensing values as an operating frequency of the driving voltage, so that the piezoelectric actuator vibrates Resonant frequency. The vibration processing apparatus according to claim 1, wherein the frequencies corresponding to the sensing values of different sizes are one-to-one corresponding to an original resonant frequency at which the piezoelectric actuator is shipped. The equal difference increase and decrease frequency is selected. The vibration processing apparatus according to claim 2, wherein, when the vibration driving module operates in a scanning mode, the analysis control unit sequentially sets the frequency of the driving voltage to the frequencies generated by the selection, and When the vibration driving module operates in a resonant mode, the analysis control The system sets the frequency of the driving voltage to the operating frequency. The vibration processing device of claim 1, wherein the magnitude of the sensed value output by the current sensor is synchronously changed according to a magnitude of the drive current sensed by the current sensor; The vibration driving module further includes: a phase difference detector electrically connected to the analysis control unit to receive the driving voltage, and electrically connecting the current sensor to receive the sensing value, and outputting an indication of the driving voltage and the sense a phase comparison signal of a phase difference between the measured values; the analysis control unit further receives the phase difference comparison signal, and determines a voltage phase of the driving voltage according to the phase difference comparison signal. The vibration processing device of claim 4, wherein the analysis control unit comprises: a controller for outputting a control signal; and a voltage controlled oscillator electrically connected to the controller to receive the control signal, And being controlled by the control signal to output an oscillation signal, wherein the frequency of the oscillation signal is controlled by the frequency of the control signal; a power amplifier electrically connected to the voltage controlled oscillator to receive the oscillation signal, and the oscillation signal is The amplitude is amplified to become an enhanced oscillation signal and output; and an impedance matching device is electrically connected to the power amplifier to receive the enhanced oscillation signal, and converts the enhanced oscillation signal into the driving voltage and outputs. A vibration driving module suitable for a vibration processing device, the vibration plus The device includes a piezoelectric actuator that receives a driving voltage and generates vibration according to the frequency of the driving voltage, and generates a driving current of a magnitude varying with a frequency of the driving voltage, the vibration driving The module electrically connects the piezoelectric actuator and generates the driving voltage, and includes: a current sensor for sensing a magnitude of the driving current corresponding to the plurality of different frequencies, and according to the sensed Each of the driving currents outputs a sensing value; and an analysis control unit is electrically connected to the current sensor to receive each sensing value, and stores each sensing value, and each sensing value corresponds to The frequency, and the analysis control unit sets the frequency corresponding to the largest one of the stored sensing values as an operating frequency of the driving voltage, so that the piezoelectric actuator vibrates at a resonant frequency . According to the vibration driving module of claim 6, wherein the frequencies corresponding to the sensing values of different sizes are one-to-one corresponding to an original resonant frequency when the piezoelectric actuator is shipped from the factory. The initial difference increase and decrease frequency selection is generated. According to the vibration driving module of claim 7, wherein the vibration control module operates in a scanning mode, the analysis control unit sequentially sets the frequency of the driving voltage to the frequencies generated by the selection, When the vibration driving module operates in a resonance mode, the analysis control unit sets the frequency of the driving voltage to the operating frequency. According to the vibration driving module of claim 6, wherein the magnitude of the sensing value output by the current sensor is synchronously changed according to the magnitude of the driving current sensed by the current sensor; The vibration driving module further includes: a phase difference detector electrically connected to the analysis control unit to receive the driving voltage, and electrically connecting the current sensor to receive the sensing value, and outputting an indication of the driving voltage and the a phase comparison signal of a phase difference between the sensed values; the analysis control unit further receives the phase difference comparison signal, and determines a voltage phase of the driving voltage according to the phase difference comparison signal. A frequency modulation method is applied to be executed by a vibration driving module for generating a driving voltage to be supplied to a piezoelectric actuator, so that the piezoelectric actuator generates vibration according to the frequency of the driving voltage. The frequency modulation method includes: (A) sensing a magnitude of the driving current corresponding to a plurality of different frequencies, and outputting a sensing value according to the sensed magnitude of each driving current; and (B) storing each The sensing value, and the frequency corresponding to each of the sensing values, and the analysis control unit sets the frequency corresponding to the largest one of the stored sensing values as an operating frequency of the driving voltage.