KR100659967B1 - Sound wave levitation apparatus and method of detecting a resonance frequency thereof - Google Patents

Abstract

(Problem) Provided is an acoustic wave flotation device capable of accurately detecting a resonant frequency when an elongated vibrating body is excited by an oscillator on the excitation side, and capable of vibrating the vibrating body more efficiently than a conventional device.

(Solution means) The sound wave levitation device excites the vibrator on the aftershock side connected to one end of the long vibrating body, and supports the object by using the radial pressure of the ultrasonic wave caused by the vibration of the vibrating body. The power supply device 23 includes constant voltage control means for constant voltage control of the oscillator 22 for exciting the oscillator on the excitation side, and frequency sweeping means for sweeping the output of the oscillator 22 in constant voltage control over a predetermined frequency range. The control apparatus 29 which comprises is comprised. The controller 29 stores in the memory 32 the frequency of the peak corresponding to at least the maximum amplitude of the vibrating body and the frequency of the peak corresponding to the second largest amplitude among the output peaks of the voltage sensor at the time of frequency sweep. .

Sound wave, flotation, resonant frequency

Description

SOUND WAVE LEVITATION APPARATUS AND METHOD OF DETECTING A RESONANCE FREQUENCY THEREOF

1 is a schematic perspective view of an object support conveying apparatus according to a first embodiment.

2 is a schematic side view of an object support conveying apparatus.

3 is a block circuit diagram of a driving power supply.

4 is a schematic diagram showing a driving power supply and a monitor;

5 is a schematic perspective view of an object support conveying apparatus according to a second embodiment.

6 is a schematic perspective view of an object support conveying apparatus in another embodiment.

(Description of Major Symbols in the Drawing)

M ... object

11 ... object floating conveying device as a sound wave floating device

12 ... diaphragm as vibrating body

13, 14 ... vibrators

15 ... soul

22 ... oscillator

26. Voltage sensor as vibration state detecting means

DC constant voltage generation circuit constituting the constant voltage control means and the constant current control means

29 A control device comprising a constant voltage control means and a constant current control means, and a frequency sweeping means

32 Memory as a storage means

35 Control monitor as display device

36a, 36b..Vibration pick-up as vibration detection means

[Patent Document 1] Japanese Unexamined Patent Publication No. 2003-126778 (paragraphs [0020], [0021], [0024], FIG. 1 of the specification)

The present invention relates to a method for detecting a resonant frequency of a sound wave support device and a sound wave support device, and more particularly, of a sound wave support device and a sound wave support device for supporting an object by using the radial pressure of the ultrasonic wave by the vibration of a long vibrating body. Resonance frequency detection method. In this specification, the "long vibrating body" means that the length of a vibrating body is the length of 10 wavelengths or more of a vibration wavelength.

On one end of the long vibrating body, an oscillator on the side of the excitation (vibration side) is formed, and on the other end, an oscillator on the water receiving side is generated, generating a traveling wave to the vibrating body, and an object on the surface of the vibrating body by the radial pressure. The object lifting conveying apparatus (sound wave flotation apparatus) which conveys in the state which floated the is proposed (for example, refer patent document 1.). This apparatus forms a vibrator on the excitation side at one end of the vibrating body and forms a vibrator on the other side at the other end using a long flat vibrating body. The oscillator on the excitation side is connected to an oscillator for excitation, and a traveling wave is generated in the vibrating body and conveyed in a state in which an object is supported on the surface of the vibrating body by the radial pressure.

In the object support conveying apparatus of patent document 1, the lang-ju bang type vibrator using a piezoelectric element (piezo element) is used as an oscillator of an excitation side. Then, in the stripe mode, by exciting the vibrator at the resonance frequency at which the wave side amplitude is maximum, the vibrating body is vibrated to the required intensity (amplitude), and the signal of the vibration state detecting means for detecting the vibration state of the wave side is fed back. To control the oscillator. As said vibration state detection means, the voltage sensor which detects the output voltage of the piezoelectric element which comprises the oscillator on the water receiving side is formed. The control is performed so that the voltage on the water receiving side becomes equal to or larger than the maximum or preset setting value, and is substantially constant current control.

When the excitation side and the receiving side of the vibrating body are separated from each other, such as a long plate, even if the vibrating body vibrates well on the exciting side, vibration may not be satisfactorily performed on the receiving side. In addition, since the long vibrating body has a plurality of intrinsic values of the resonant frequency, even if the vibration side vibrates in a desired mode (for example, a striped mode), the vibration side may vibrate in a state other than the desired mode. In particular, when generating a standing wave in the vibrating body, it is preferable to excite at the resonance point, but when generating a traveling wave, it is better to excite the resonance side with a predetermined phase difference in the vicinity of the resonance point instead of the resonance point. It is necessary to feed back the vibration state of.

In the apparatus of Patent Literature 1, the vibrator is excited at a resonant frequency in which the wave side amplitude is maximum in the stripe mode. For this purpose, prior to the normal operation of the apparatus, it is necessary to perform frequency sweep to sweep the output of the oscillator over a predetermined frequency range to detect the resonance frequency at which the wave side amplitude is maximum in the stripe mode. In the conventional apparatus, since the oscillator is controlled by the constant current control, the frequency sweep is also performed by the constant current control. However, when the frequency sweep is performed by the constant current control, the vibration occurs at a position slightly shifted from the resonance point, and as a result, the detection accuracy of the resonance frequency is low, and fine adjustment is necessary to effectively vibrate the vibrating body. Also, depending on conditions such as the length and load of the vibrating body, the end of the vibrating body must be fixed when the vibrating body is excited at a resonant frequency at which the wave amplitude is maximum in the stripe mode. It may not vibrate uniformly from a point to the end side of a vibrating body).

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and its first object is to accurately detect a resonant frequency when exciting a long vibrating body with an oscillator on the side of the excitation, and thus, the vibrating body can be efficiently The present invention provides a sound wave flotation device capable of vibrating. Moreover, a 2nd object is to provide the resonance frequency detection method of the acoustic wave flotation apparatus which can detect the resonance frequency at the time of exciting a long vibrating body by the vibrator of an excitation side.

In order to achieve the first object, the invention described in claim 1 includes: a constant voltage control means for controlling a constant voltage of an oscillator for exciting an oscillator on the excitation side connected to one end of a long vibrating body, and a frequency at which the output of the oscillator is preset Frequency sweep means for sweeping with constant voltage control over the entire range are provided. Further, at least vibration of vibration state detection means for outputting a detection signal corresponding to the vibration state on the water receiving side of the vibrating body, and an output peak of the vibration state detection means at the time of frequency sweep by the frequency sweeping means. Memory means for storing the frequency of the peak corresponding to the maximum amplitude of the sieve and the frequency of the peak corresponding to the second largest amplitude is provided.

In the present invention, by sweeping the output of the oscillator by the constant voltage control over the preset frequency range by the frequency sweeping means, it is possible to accurately detect all the resonance frequencies within the frequency range. Then, at least the frequency of the peak corresponding to the maximum amplitude of the vibrating body on the receiving side of the vibrating body and the frequency of the peak corresponding to the second largest amplitude are stored in the storage means. Therefore, when the apparatus is normally operated, when the condition where the amplitude at the receiving side of the vibrating body is maximum is not a condition for exciting the vibrating body in a proper state, the vibrating body is excited by referring to the second resonance frequency as a reference. It can be easily changed to the excitation condition that vibrates in an appropriate state.

Invention of Claim 2 is equipped with the constant current control means which carries out constant current control of the said oscillator in invention of Claim 1, and the said oscillator is constant current controlled at the time of normal operation. Here, "normal operation" means the case of exciting a vibrating body in order to float or convey an object.

In the present invention, by driving the oscillator under constant voltage control, it is possible to accurately detect the resonance frequency when the long vibrating body is excited by the vibrator on the excitation side. In addition, during the normal operation, since the oscillator is controlled by constant current, it becomes easy to drive the vibrating body at a constant amplitude.

In invention of Claim 3, in the invention of Claim 2, the said constant current control means and the said constant voltage control means are comprised by the same circuit. In the present invention, compared with the case where the constant current control means and the constant voltage control means each have independent circuit configurations, an increase in the size and weight of the device can be suppressed, and the manufacturing cost can be reduced.

In the invention according to claim 4, the invention according to any one of claims 1 to 3, wherein the storage means includes at least a resonance frequency among information detected at the time of frequency sweep by the frequency sweeping means, and the resonance frequency. The numerical value corresponding to the amplitude of the said vibrating body in is stored. Here, the "numeric value corresponding to the amplitude" is not limited to the numerical value of the detection signal output from the vibration state detecting means itself, and the numerical value obtained by multiplying the amplitude value or the amplitude value calculated from the numerical value of the detection signal and the like. Include.

In the present invention, since the numerical value corresponding to the resonant frequency and the amplitude of the vibrating body at the resonant frequency is stored in the storage means, the excitation condition of the vibrating body to be in a suitable vibrating state is selected based on the information. It becomes easy.

Invention of Claim 5 is provided with the display apparatus which displays the resonance frequency and the vibration mode of at least the said vibrating body in the invention of any one of Claims 1-4. Therefore, in the present invention, the resonant frequency and vibration mode of the vibrating body can be confirmed by the display device, and it can be easily confirmed whether the device is operating in a desired state.

In the invention according to claim 6, in the invention according to any one of claims 1 to 5, the vibrating body is fixed to the horn, and the vibration of the end side is detected from a fixed position with respect to the horn of the vibrating body. Vibration detection means is provided. In the present invention, it is possible to confirm whether or not the vibrating body is vibrating to both ends thereof, and it is easy to change the excitation condition so as to prevent the excitation from continuing in a state different from that in which the vibrating body vibrates to both ends thereof.

In order to achieve the second object, in the resonance frequency detection method of the invention according to claim 7, the oscillator on the excitation side connected to one end of the long vibrating body is excited and the radial pressure of the ultrasonic wave caused by the vibration of the vibrating body is reduced. In the acoustic wave flotation device for supporting an object, the output of the oscillator for exciting the vibrator on the excitation side is sweeped with constant voltage control over a predetermined frequency range. Then, the peak of the detection signal corresponding to the resonance state on the receiving side of the vibrating body is detected to detect the resonance frequency. In the present invention, the output of the oscillator is sweeped with constant voltage control over a predetermined frequency range, the peak of the detection signal corresponding to the resonance state on the receiving side of the vibrating body is detected to detect the resonance frequency. Therefore, the resonance frequency at the time of exciting the long vibrating body with the vibrator on the excitation side can be detected correctly.

Best Mode for Carrying Out the Invention

(1st embodiment)

EMBODIMENT OF THE INVENTION Hereinafter, 1st Embodiment which actualized this invention to the object flotation conveying apparatus is demonstrated according to FIGS. 1 is a schematic perspective view of an object flotation conveying apparatus, FIG. 2 is a schematic side view of the object flotation conveying apparatus, and FIG. 3 is a block circuit diagram of a driving power supply.

As shown in FIG. 1 and FIG. 2, the object flotation carrier 11 as the sound wave flotation device is provided with a diaphragm 12 as a long vibrating body. The diaphragm 12 is formed in rectangular flat form. One end side of the diaphragm 12 (the left end side of FIGS. 1 and 2), the oscillator 13 of the excitation side, and the other end side of the oscillator 14, the screws not shown at the tip of the horn 15, respectively. It is fastened by (16). The horn 15 is formed in a flat substantially rectangular parallelepiped shape, and is attached to the diaphragm 12 in a state perpendicular to the longitudinal direction at both ends in the longitudinal direction thereof.

Each horn 15 is fixed to each vibrator 13, 14 on the surface opposite to the surface on which the diaphragm 12 is fastened. That is, the horn 15 constitutes a part of the vibrator 13. The front end surface of the horn 15 is formed in the plane orthogonal to the axial direction of the vibrators 13 and 14, and is arrange | positioned in the state which the center axis of the horn 15 and the vibrators 13 and 14 extend in a perpendicular direction. .

The so-called rouge bang type vibrators are used for the vibrators 13 and 14, and are equipped with a pair of ring-shaped piezo elements 17a and 17b. The ring-shaped electrode plate 18 is disposed between both piezoelectric elements 17a and 17b, and the metal blocks 19a and 19b abutting the surface on the opposite side to the side on which the piezoelectric elements 17a and 17b abut on the electrode plate 18. ), The vibrators 13 and 14 are comprised by tightening and fixing with the bolt which is not shown in figure. The bolt is screwed into the screw hole (not shown) formed in the metal block 19a from the metal block 19b side. Both metal blocks 19a and 19b are in a state where they are connected to each other via bolts.

2, the flange 20 is formed in the upper end of the metal block 19a, and the metal block 19a is not shown in the state fitted to the hole (not shown) formed in the base plate 21, and is not shown in figure. By this, the flange 20 is fixed to the base plate 21.

The vibrator 13 which excites the horn 15 fastened to the excitation side of the diaphragm 12 is connected to the power supply device 23 provided with the oscillator 22. The electrode plate 18 is connected to the oscillator 22 via the wiring 24a, and the ground terminal of the oscillator 22 is connected to the metal block 19b via the wiring 24b.

Piezoelectric elements 17a and 17b as elements for energy conversion of the vibrator 14 fastened to the water wave side of the diaphragm 12 are connected to a load circuit 25 as energy conversion means consisting of a resistor R and a coil L. And the electrode plate 18 and the metal block 19b are respectively connected. The vibrator 14 is equipped with the voltage sensor 26 which detects the voltage generate | occur | produced in the piezo element 17a, 17b. The voltage sensor 26 constitutes vibration state detection means for outputting a detection signal corresponding to the vibration state on the water wave side of the diaphragm 12.

As shown in FIG. 3, the power supply device 23 includes a DC constant voltage generation circuit 27, an inverter circuit 28, a control device 29, and a current sensor 30. The DC constant voltage generation circuit 27 is configured to be capable of converting input power into a predetermined DC constant voltage, and is configured to be able to set an upper limit of the conversion voltage. The inverter circuit 28 inputs the DC voltage output from the DC constant voltage generation circuit 27 and converts it into AC. The inverter circuit 28 is comprised so that an output voltage can also be changed with a transformer, for example. The current sensor 30 detects the amount of current output from the inverter circuit 28 and flowing to the load, that is, the vibrator 13. The inverter circuit 28 constitutes an oscillator 22.

In this embodiment, the constant voltage control means for constant voltage control of the oscillator 22 which excites the oscillator 13 on the excitation side, and the constant current control means for constant current control of the oscillator 22 include a DC constant voltage generation circuit 27 and The control apparatus 29 is comprised. Moreover, the control apparatus 29 comprises the frequency sweeping means which sweeps the output of the oscillator 22 by constant voltage control over the preset frequency range.

The control device 29 is provided with a CPU (central processing unit) 31 and a memory 32 as a storage means. The voltage sensor 26 and the current sensor 30 are connected to the CPU 31 via an A / D converter and an interface (both not shown). The controller 29 performs constant current control so that the set current value becomes normal during normal operation. Moreover, the control apparatus 29 is comprised so that the resonance frequency of the diaphragm 12 may be detected before normal operation. The controller 29 sweeps the output of the oscillator 22 in the constant voltage control over a predetermined frequency range, and resonates at the receiving side of the diaphragm 12 based on the detection signal of the voltage sensor 26. The resonance frequency is detected by detecting the peak of the voltage corresponding to the state.

In the constant current control, the control device 29 inputs the detection signal of the current sensor 30, and if the detection signal is smaller than the set current value, the command signal for increasing the output voltage to the DC constant voltage generation circuit 27. Is output to increase the output current value of the inverter circuit 28. On the contrary, when the detection signal of the current sensor 30 is larger than the set current value, the command signal for reducing the output voltage is output to the DC constant voltage generation circuit 27 to reduce the output current value of the inverter circuit 28.

When performing voltage control, the control apparatus 29 narrows the upper limit of the output voltage set value in the DC constant voltage generation circuit 27 (for example, compresses it to 10% of the maximum value), and outputs the inverter circuit 28. Increase the constant current setting (for example, 90% of the maximum value). When control is performed in this state, the output current of the inverter constant current circuit 27 is attempted to be controlled to the set constant current value, and the output voltage of the DC constant voltage generation circuit 27 is increased. However, this is limited because the voltage upper limit setting is narrowed. As a result, the output of the DC constant voltage generation circuit 27 becomes constant at the voltage upper limit set value, thereby making constant voltage control.

The memory 32 stores a map indicating the relationship between the voltage upper limit set value in the case of constant voltage control and the current supplied to the load, so that the appropriate voltage upper limit set value in the case of constant voltage control is changed by the load. It is. The map is obtained by performing a test in advance.

The controller 29 stores in the memory 32 the information detected at the time of frequency sweep performed prior to normal operation. As information, the frequency of the peak corresponding to at least the maximum amplitude of the diaphragm 12 among the output peaks of the voltage sensor 26 and the frequency of the peak corresponding to the second largest amplitude, that is, the maximum amplitude of the diaphragm 12 among the resonant frequencies. And a numerical value corresponding to the resonance frequency corresponding to the second largest amplitude and the amplitude of the diaphragm 12 at the resonance frequency. In this embodiment, the voltage V2 output from the voltage sensor 26 is stored as a numerical value corresponding to the amplitude. The controller 29 stores all the resonant frequencies and the voltage V2 corresponding thereto. As the information, there is a phase of the voltage V1 supplied to the vibrator 13 on the excitation side and the phase of the voltage V12 output from the voltage sensor 26 based on the vibration of the vibrator 14 on the water wave side.

As shown in FIG. 4, the control apparatus 29 is equipped with the communication port 33, and the control monitor 35 as a display apparatus is controlled by the control cable 34 connected to the communication port 33. As shown in FIG. It is connected to (29). The control monitor 35 is provided with the microcomputer not shown in figure, and is displayed so that the information memorize | stored in the memory 32 of the control apparatus 29, and the information obtained by processing the information are displayed on a screen. Information to be displayed includes at least the resonance frequency of the diaphragm 12, the vibration mode when the diaphragm 12 is excited at the resonance frequency, the amplitude of the diaphragm 12, the phase difference between the voltage V1 and the voltage V2, and the like. have.

Since the vibration mode, that is, whether the diaphragm 12 is vibrating in the stripe mode or the lattice mode, can be discriminated from the phase difference between the voltage V1 and the voltage V2, the control monitor 35 uses the communication cable 34. Based on the phase information of the voltage V1 and the voltage V2 obtained from the control device 29, it is judged whether it is the stripe mode or the lattice mode, and the vibration mode is displayed.

The screen shown in FIG. 4 shows an example of a display screen at the time of constant voltage control for resonance frequency detection. In the screen of Fig. 4, a graph in which the vertical axis is the voltage V2 and the horizontal axis are the frequencies, and the frequency of the peak position of the graph, that is, the numerical value of the resonance frequency are displayed in letters. When the resonance frequencies cannot all be displayed on the graph at the same time, they are divided into a plurality of times or scrolled to display the screen. In addition, regarding the part of the resonance frequency which becomes the vibration of a stripe mode, the indication which distinguishes it is made. As an example of the display for distinguishing the stripe modes, there is a method of displaying the peaks of the resonant frequencies in the stripe mode in different colors, or netting them in the range of frequencies vibrating in the stripe mode around the peaks.

The control monitor 35 displays the information corresponding to the vibration mode, the resonance frequency, the value of the amplitude of the diaphragm 12, the phase difference between the voltage V1 and the voltage V2 in the driving state during normal operation. In the constant voltage control for resonant frequency detection, the control monitor 35 displays all the detected resonant frequencies, the amplitude of the diaphragm 12, the vibration mode, the phase difference between the voltage V1 and the voltage V2.

As the excitation condition at the time of normal operation, the control device 29 has the maximum resonance of the amplitude of the diaphragm 12 among the frequencies at which the diaphragm 12 vibrates in the stripe mode among the resonant frequencies detected by the resonant frequency detection process. The oscillator 22 is subjected to constant current control so as to excite the oscillator 13 by selecting an excitation condition that becomes a frequency. However, the operator can instruct the control device 29 to excite the vibrator 13 at the selected resonant frequency among all the resonant frequencies by selecting the resonant frequency displayed on the control monitor 35.

Next, the effect | action of the object floating conveyance apparatus 11 comprised as mentioned above is demonstrated.

Prior to normal operation, the resonant frequency is detected. The control apparatus 29 sweeps the output of the oscillator 22 by constant voltage control over the preset frequency range, and detects all the resonant frequencies. The values of all detected resonant frequencies, the values corresponding to the amplitude of the diaphragm 12 at each resonant frequency, and the phases of the voltage V1 and the voltage V2 are stored in the memory 32. Then, the control monitor 35 displays the detected resonant frequency, the vibration mode at each resonant frequency, and the phase difference between the voltage V2, the voltage V1, and the voltage V2 as numerical values corresponding to the amplitude of the diaphragm 12.

The operator checks the display of the control monitor 35 and selects the resonance frequency of normal operation. Then, normal operation is performed at the selected resonance frequency. When the operator does not select the resonant frequency, the control unit 29 has the amplitude of the diaphragm 12 being the maximum resonant frequency among the frequencies at which the diaphragm 12 vibrates in the stripe mode among the detected resonant frequencies. The excitation condition is selected, and normal operation is performed under the excitation condition.

In the normal operation, the oscillator 22 is controlled by the constant current control. The oscillator 22 is driven by the control signal from the control device 29, and the vibrator 13 is excited at a frequency near the selected resonant frequency (for example, around 20 kHz). When the vibrator 13 is excited, the horn 15 vibrates longitudinally, and the diaphragm 12 is excited through the horn 15 to cause bending vibration. By the radial pressure of the sound waves radiated from the diaphragm 12, the object M is suspended from the surface of the diaphragm 12. The flotation distance is from 10 to 100 μm.

Vibration of the diaphragm 12 is transmitted to the vibrator 14 of the water wave side, and the vibration energy which is mechanical energy is converted into electrical energy by the piezo elements 17a and 17b which comprise the vibrator 14. This electric energy is converted into Joule heat by the resistance R of the load circuit 25 and dissipated. Therefore, the vibration wave which arises in the diaphragm 12 becomes a traveling wave which progresses in one direction from an excitation side toward a water wave side (in this embodiment, it is a traveling wave which advances from the vibrator 13 side to the vibrator 14 side), The object M is conveyed from the excitation side of the diaphragm 12 to the water wave side in the floating state.

When the control apparatus 29 confirms that the object M has reached the stop position by the detection signal of the object detection sensor which is not shown in figure, the state which generate | occur | produces the standing wave to the diaphragm 12 the output of the oscillator 22 is confirmed. Change to Then, the object M is decelerated and stopped in the floating state.

The controller 29 controls the output of the oscillator 22 so that traveling waves generated from the vibrator 13 side to the vibrator 14 side are generated in the diaphragm 12. The control unit 29 is a phase difference (for example, 90 °) in which a phase difference in which a phase difference between a voltage V1 input to the oscillator 13 on the excitation side and a voltage V2 output from the oscillator 14 on the receiving side is preset is easily generated. The output of the oscillator 22 is controlled so that the output voltage of the oscillator 14 on the water receiving side becomes equal to or more than a predetermined value. The output voltage and phase of the oscillator 14 on the water receiving side are detected by the output signal of the voltage sensor 26.

In the vibrator 13 using the piezoelectric element, in order to vibrate efficiently in the state which generates the standing wave in the diaphragm 12, it is necessary to excite the vibrator 13 by a resonance frequency. On the other hand, in order to vibrate in the state which generate | occur | produces a traveling wave efficiently in the diaphragm 12, it is preferable to excite the vibrator 13 at the frequency slightly shifted from the resonant frequency instead of the resonant frequency. Then, the control device 29 is a phase difference between the voltages V1 and V2 of the oscillators 13 and 14 on the excitation side and the receiving side for efficiently generating traveling waves set on the basis of the selected resonance frequency among the plurality of resonance frequencies. The oscillator 22 is controlled to excite the vibrator 13 at the frequency of the vibrator 13. When the environment of the object support and conveying apparatus 11 changes, the resonant frequency and the phase difference of the voltage V1 and the voltage V2 which were suitable at the time of a resonance frequency detection may shift from an appropriate excitation condition.

Since the controller 29 always detects the vibration state of the oscillator 14 on the water receiving side by inputting the output from the voltage sensor 26, the control device 29 can accurately grasp the vibration state from the phase and magnitude of the voltage V2. have. Then, when the vibration state of the vibrator 14 is weakened or the like is shifted from the state in which the traveling plate is efficiently generated in the diaphragm 12, the phase of the voltage V1 output from the oscillator 22 is changed or the constant current control is set. Sometimes the current value is high.

And when it is confirmed from the output of the voltage sensor 26 that the vibration state of the vibrator 14 returned to the state which generate | occur | produces a traveling wave efficiently, driving of the oscillator 22 is continued on that condition.

This embodiment has the following effects.

(1) constant voltage control means (direct current constant voltage generating circuit 27 and controller 29) for constant voltage control of oscillator 22 for exciting the oscillator 13 on the excitation side connected to one end of long diaphragm 12; And a frequency sweeping means (controller 29) for sweeping the output of the oscillator 22 in a constant voltage control over a predetermined frequency range. The vibration state on the water wave side of the diaphragm 12 is also provided. And a vibration state detecting means (voltage sensor 26) for outputting a detection signal (voltage V2) to be described. Therefore, by the control of the control device 29, the output of the oscillator 22 is spread over a predetermined frequency range. By sweeping with constant voltage control over, all the resonant frequencies within the frequency range can be detected accurately, and the vibration state of the water wave side due to the variation of the load of the vibrometer due to the difference in the weight of the object M or the like. Even change, may set the excitation condition of the excitation-side transducer (13) on the basis of the correct resonant frequency.

(2) All the resonant frequencies detected at the frequency sweep and the numerical values corresponding to the amplitude of the diaphragm 12 at each resonant frequency are stored in the memory 32. Therefore, when operating the object support conveying apparatus 11 normally, when the condition which the amplitude in the water wave side of the diaphragm 12 becomes the maximum is not a condition which excites the diaphragm 12 to an optimal state, the diaphragm ( 12) can be easily changed to an excitation condition that vibrates to an appropriate state.

(3) A constant current control means (a DC constant voltage generating circuit 27 and a control device 29) for controlling the constant current of the oscillator 22 is provided so that the oscillator 22 is subjected to constant current control during normal operation. Since the oscillator 22 is subjected to constant current control, it is easy to drive the diaphragm 12 at a constant amplitude.

(4) The constant current control means and the constant voltage control means are constituted by the same circuit. Therefore, compared with the case where the constant current control means and the constant voltage control means each have independent circuit configurations, an increase in the size and weight of the device can be suppressed, and the manufacturing cost can be reduced.

(5) Since the memory 32 stores at least the resonant frequency among the information detected at the time of frequency sweep and the numerical value corresponding to the amplitude of the diaphragm 12 at the resonant frequency, it is optimal based on the information. It is easy to select the excitation condition of the diaphragm 12 which is in a vibration state of.

(6) A control monitor 35 for displaying at least the resonance frequency and vibration mode of the diaphragm 12 is provided. Therefore, the operator can confirm the resonant frequency and vibration mode of the diaphragm 12 with the control monitor 35, and can easily confirm whether the object support conveying apparatus 11 is operating in the desired state.

(7) The control monitor 35 displays the vibration mode, the resonance frequency, the amplitude of the diaphragm 12, and the phase difference between the voltage V1 and the voltage V2 in the operation state during normal operation. Therefore, the operator can easily determine whether the current excitation condition is in an appropriate state when the driving environment is changed.

(8) In constant voltage control for resonant frequency detection, the control monitor 35 displays all the detected resonant frequencies, numerical values corresponding to the amplitude of the diaphragm 12, the vibration mode, and the phase difference between the voltage V1 and the voltage V2. . Therefore, it becomes easy for an operator to select the resonance frequency corresponding to an appropriate excitation condition based on the display.

(9) The control apparatus 29 excites the vibrator 13 to generate a traveling wave to the long diaphragm 12. At this time, since the vibration state of the oscillator 14 on the water wave side is detected and fed back to the voltage sensor 26, the control unit 29 determines whether the phase difference between the vibration of the excitation side and the water wave side is suitable for generating traveling waves. You can check whether or not.

(10) Since the energy conversion element (voltage sensor 26 for detecting the voltage V2 output from the piezoelectric elements 17a, 17b) is used as the vibration state detecting means for detecting the vibration state of the oscillator 14 on the water receiving side. The vibration state of the vibrator 14 on the water wave side can be detected easily.

(11) As the vibrators 13 and 14 on the excitation side and the water receiving side, vibrators having the same configuration including piezo elements 17a and 17b and the like are used. Therefore, it becomes easy to electrically detect the vibration state of the vibrator 14 on the water wave side. In addition, by connecting the load circuit 25, it becomes easy to stably generate a traveling wave.

(12) The vibration energy, which is mechanical energy, is converted into electrical energy by the piezoelectric elements 17a and 17b constituting the oscillator 14 on the water receiving side, and the electrical energy is converted by the resistance R of the load circuit 25. Converted to Joule heat and dissipated. Therefore, compared with the configuration in which the vibration energy is not consumed in the load circuit 25, it is possible to easily generate a traveling wave from the excitation side to the water receiving side.

(2nd embodiment)

Next, 2nd Embodiment is described based on FIG. This embodiment differs from the first embodiment in that the vibration detection means is provided at both ends of the diaphragm 12. About the same part as 1st Embodiment, the same code | symbol is attached | subjected and the detailed description is abbreviate | omitted.

In order to detect the vibration of the end side from the fixed location with respect to the horn 15 of the diaphragm 12, both ends of the diaphragm 12 vibrate as a vibration detection means from the fixed location with respect to the horn 15 at the end side lower surface. Pickups 36a and 36b are fixed. The vibration pick-up 36a is fixed to the excitation side edge part of the diaphragm 12, and the vibration pick-up 36b is fixed to the water receiving side edge part of the vibration plate 12. As shown in FIG. The detection signals of the vibration pickups 36a and 36b are input to the control device 29.

The controller 29, in addition to the same information as in the first embodiment, when frequency sweeping is performed by the constant voltage control to detect the resonance frequency, the detection information of the vibration pickups 36a and 36b, that is, the diaphragm The numerical values corresponding to the amplitudes of both ends of (12) are also stored in the memory 32. The control monitor 35 has an end of the diaphragm 12 in addition to the detected resonant frequency, the vibration mode at each resonant frequency, the numerical value corresponding to the amplitude of the diaphragm 12, and the phase difference between the voltage V1 and the voltage V2. The numerical value corresponding to the amplitude as the vibration state of is displayed. The output voltage V3 of the vibration pickup 36a and the output voltage V4 of the vibration pickup 36b are displayed as a numerical value corresponding to the amplitude as the vibration state of the end of the vibration plate 12.

In the case where the diaphragm 12 is vibrated at a resonant frequency at which the amplitude of the wave receiving side is maximum in the stripe mode, it may not always vibrate even to the end of the diaphragm 12. The vibration state of the vibrator 14 on the water receiving side of the diaphragm 12 is accurately reflected with respect to the vibration between the portions fixed to the horn 15 of the diaphragm 12, from the portion fixed to the horn 15 to the free end side. As for the vibration of, it is not accurately reflected. Therefore, only by monitoring the numerical value of the voltage V2 output from the voltage sensor 26, reliability is low in grasping the vibration state of the diaphragm 12 whole. However, in this embodiment, it is possible to reliably determine whether or not the vibration pick-up 36a, 36b vibrates uniformly to the end of the vibration plate 12.

Therefore, in this 2nd Embodiment, in addition to having the same effect as the effects (1)-(12) of the said 1st Embodiment, it has the next effect.

(13) Vibration detecting means (vibration pick-ups 36a, 36b) are provided for detecting the vibration on the end side from the fixed position with respect to the horn 15 of the diaphragm 12. Thus, the diaphragm 12 has its both ends. It is possible to confirm whether or not it is vibrating up to, and it is easy to change the excitation condition so as to prevent the excitation from continuing in a state different from the state in which the diaphragm 12 vibrates to both ends thereof. Since the vibrator 13 can be excited on the conditions which make it stably and uniformly vibrate efficiently, when conveying the object M by connecting several object support conveying apparatuses 11 in series, a conveyance direction upstream side The object M can be stably supported also at the connecting portion from the diaphragm 12 of the diaphragm 12 to the downstream diaphragm 12.

(14) Since the vibration pickups 36a and 36b fixed to the diaphragm 12 are used as the vibration detecting means, the vibration can be detected with high precision with a compact configuration.

Embodiment is not limited to the above, For example, you may comprise as follows.

○ As a vibration state detection means for outputting a detection signal corresponding to the vibration state on the water wave side of the diaphragm 12, the voltage generated in the piezoelectric elements 17a and 17b constituting the water wave oscillator 14 is detected. Instead of the voltage sensor 26 described above, a vibration pickup may be formed on the water wave side of the diaphragm 12, and the detection signal may be replaced with the voltage V2.

○ The vibration state detecting means for outputting a detection signal corresponding to the vibration state on the water wave side of the diaphragm 12 is that the water wave side of the diaphragm 12 vibrates when the vibrator 13 on the excitation side is excited. It should just be able to detect a thing, It is not limited to the structure which detects the vibration of the water wave side of the diaphragm 12 directly, The structure which detects the vibration of the location which vibrates when the water wave side vibrates may be sufficient. Therefore, when the vibration pick-up is used as the vibration state detecting means, the mounting position is not limited to the water wave side of the vibration plate 12, but is mounted at a position other than the water wave side of the vibration plate 12, or the vibration plate 12 or the horn is mounted. You may mount in the place which vibrates corresponding to the vibration of (15). In the case where the diaphragm 12 is mounted at a place other than the water wave side, it is preferable to obtain a relationship between the detection signal and the voltage V2 in advance.

The vibration detecting means for detecting the vibration of the end side from the fixed position with respect to the horn 15 of the diaphragm 12 should just be able to output the detection signal corresponding to the vibration of the said end side, and the vibration pick-up 36a, 36b It is not limited to). For example, a micro horn or the like may be used to output a sound pressure signal equivalent to a vibration component, or a non-contact vibration sensor of a laser Doppler system may be used. Moreover, you may employ | adopt the same structure also in a vibration state detection means.

Instead of forming the current sensor 30 on the output side of the inverter circuit 28, the current sensor 30 is formed on the primary side of the transformer incorporated in the inverter circuit 28, and the output current of the inverter circuit 28 is obtained from the detection signal. It is good also as a structure.

Instead of forming the control monitor 35 independently of the power supply device 23, a display portion may be formed in the casing of the power supply apparatus 23, and the display portion may display information such as a resonance frequency.

○ As the control monitor 35 or the display unit, the display can be selected by a touch panel, and a screen for displaying information related to the resonance frequency is selected by touching the display of the resonance frequency displayed on the panel, or the vibrator It is good also as a structure which can select the excitation condition of (13).

○ Without the control monitor 35, communication functions to other devices or input / output functions to a transportable storage medium (various disks, memory cards, etc.) are added, and these functions are used to provide information such as resonance frequency and excitation conditions. It is good also as a structure which receives this.

The constant current control means and the constant voltage control means may be formed independently of each other.

When the traveling wave is generated in the diaphragm 12, the load circuit 25 does not consume the electrical energy converted from the vibration energy by the piezoelectric elements 17a and 17b constituting the oscillator 14 on the water wave side. You may make it.

The object flotation carrier apparatus may generate standing waves without generating traveling waves in the diaphragm 12 to support the object M, and the propulsive force to the object M may be configured to use forces other than sound waves. For example, as shown in FIG. 6, the object flotation conveyance apparatus 40 is comprised by the roller conveyor apparatus 41 and the sound wave flotation unit 42 as a sound wave flotation apparatus. In this apparatus, the object M is lifted by the action of sound waves by the sound wave flotation unit 42, but the force (pulling force) for moving (transferring) the object M is given by the roller conveyor device 41. The roller conveyor apparatus 41 is provided with the some rotation shaft 44 formed between the pair of side wall 43a of the support plate 43, and the roller 45 which rotates integrally with the rotation shaft 44. As shown in FIG. The rotating shaft 44 is rotated by the motor 46 via the belt transmission mechanism. By the standing wave generated from the diaphragm 12, the center part of the object M is suspended from the surface of the diaphragm 12. As shown in FIG. However, both ends of the object M are kept in contact with the stepped portion 45a of the roller 45. And the driving force is given to the object M by rotation of the roller 45, and the object M is conveyed along the side wall 43a. Moreover, as an object M, it is applied to conveyance of a thin glass plate (thickness 1 mm or less), for example.

○ It may be applied to an object lifting device that generates standing waves in the diaphragm 12 and keeps the object M in a floating state. In this case, the load circuit 25 for consuming the electrical energy converted from the vibration energy by the piezo elements 17a and 17b is unnecessary for the oscillator 14 on the water wave side.

○ When the object M to be conveyed is wide, a plurality of units of the diaphragm 12 and both vibrators 13 and 14 are arranged in parallel, and the vibrators 13 of each unit are parallel to a common power supply device. You may connect with In this case, the wide object M can be conveyed by the some diaphragm 12 in the stable support state.

In the object-supporting conveying apparatus 11 which generates a traveling wave, both the vibrators 13 and 14 connected to the one end side and the other end side of the diaphragm 12 are comprised so that switchable connection is possible to the oscillator 22, and the excitation side You may comprise so that a water wave side can switch. In this case, the traveling direction of the traveling wave can be changed from one end side to the other end side or the other end side to one end side of the diaphragm 12 by switching the connection state of the oscillator 22. Therefore, when conveying the object M in the floating state, by switching the direction of the traveling wave, it becomes easy to apply the braking to the object M in motion in the floating state and stop it at a predetermined position.

The shape of the horn 15 is not limited to the flat rectangular parallelepiped shape, but may be a shape in which the tip side such as a cylinder shape or a truncated cone shape is tapered.

The fixing of the diaphragm 12 to the horn 15 is not limited to the fastening by the screw 16, and may use an adhesive agent, or may fix by soldering or welding.

The following technical idea (invention) can be grasped | ascertained from the said embodiment.

(1) In the invention according to any one of Claims 1 to 6, the frequency sweeping means performs frequency sweeping before normal operation, and all resonant frequencies are stored in the storage means.

(2) In the invention according to any one of claims 1 to 6, the vibration state detecting means is a voltage sensor capable of detecting a voltage and a phase corresponding to the vibration state of the water wave side.

In addition, in this specification, the "water wave side of a vibrating body" means the position which is farther from the vibrator of an excitation side with respect to the position of the vibrating body corresponding to the fixed part connected to the vibrating body, and the fixed part connected to the vibrating body in the position away from the vibrator of the excitation side it means.

According to the present invention, in the acoustic wave flotation device, the resonance frequency when the long vibrating body is excited by the vibrator on the excitation side can be detected accurately.

Claims (7)

An acoustic wave support device for exciting an oscillator on the excitation side connected to one end of a long vibrating body to support an object by using the radial pressure of ultrasonic waves caused by the vibration of the vibrating body, Constant voltage control means for constant voltage controlling an oscillator for exciting the vibrator on the excitation side; Frequency sweep means for sweeping the output of the oscillator with constant voltage control over a predetermined frequency range; Vibration state detection means for outputting a detection signal corresponding to the vibration state on the water wave side of the vibrating body; And A storage means for storing at least the frequency of the peak corresponding to the maximum amplitude of the vibrating body and the frequency of the peak corresponding to the second largest amplitude among the output peaks of the vibration state detecting means at the time of frequency sweep by the frequency sweeping means; Sound wave flotation device provided. The method of claim 1, And a constant current control means for constant current control of the oscillator, wherein the oscillator is subjected to constant current control during normal operation. The method of claim 2, And said constant current control means and said constant voltage control means are configured in the same circuit. The method according to any one of claims 1 to 3, And the numerical value corresponding to at least the resonance frequency of the information detected at the time of frequency sweep by the frequency sweeping means and the amplitude of the vibrating body at the resonance frequency in the storage means. The method according to any one of claims 1 to 3, And a display device for displaying at least the resonance frequency and vibration mode of the vibrating body. The method according to any one of claims 1 to 3, The vibrating body is fixed to the horn, and the sound wave flotation device includes vibration detection means for detecting vibration at the end side from the fixing position of the vibrating body with respect to the horn. A resonant frequency detection method of an acoustic wave stimulating device which excites an oscillator on the excitation side connected to one end of a long vibrating body and supports an object by using the radial pressure of ultrasonic waves caused by the vibration of the vibrating body. The output of the oscillator for exciting the vibrator on the excitation side is sweeped with constant voltage control over a predetermined frequency range, and the peak of the detection signal corresponding to the resonance state on the receiving side of the vibrating body is detected to detect the resonance frequency. Resonance frequency detection method of a sound wave levitation device to detect.

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