WO2011065356A1 - Functional capillary device and drive method for same - Google Patents

Abstract

Disclosed is a functional capillary device which is capable of efficiently controlling the speed of fluids within a capillary. A functional capillary device (1) is provided with: a vibrating tube body (2) in which a plurality of vibrating units (22) for inducing the radial vibration of the walls of a hollow tube (21) through which a fluid is conveyed are provided to the tube (21) at intervals along the major axis thereof; and an energy supply means (4) which supplies energy for independently vibrating the plurality of vibration units (22) to generate a travelling wave inside the tube (21). The functional capillary device (1) is characterized in that the energy supply means (4) supplies energy to the plurality of vibrating units (22) in a manner such that the phase shift in the travelling wave generated by a given vibrating unit (22), when the travelling wave reaches the position of the adjacent vibrating unit (22) in the direction that fluid travels, is countered by generating a travelling wave with a phase that is offset by the same amount as the phase shift in the adjacent vibrating unit (22).

Description

Functional capillary device and driving method thereof

The present invention relates to a functional capillary device that transports fluid in a capillary and a driving method thereof.

In recent years, using micro electro mechanical systems (MEMS) technology, μTAS (Micro Total Analysis Systems), which has been integrated and miniaturized on a chip such as an integrated circuit, a flow path for transporting fluid, a pump, etc. Development of microfluidic systems such as Chip has been actively conducted.
The microfluidic system that uses MEMS technology to place components on the chip is not easy to downsize because the flow path and pump are configured separately, and the flow path and the like are arranged on the chip. Therefore, it was difficult to deal with various applications.

Therefore, the inventors of the present application have developed a micro pump in which a flow path and a pump are integrated (see Patent Document 1 and Non-Patent Document 1).
This micropump attaches a ring-type piezoelectric element (PZT [lead zirconate titanate] element) to the surface of a silicon tube, and generates a traveling wave in the fluid in the tube by the vibration of the piezoelectric element, thereby transporting the fluid. Is what you do.

As shown in FIG. 10, a conventional micropump 60 has ring-type piezoelectric elements (PZT elements) 62 arranged at equal intervals on a silicon tube 61 that is a hollow tube, and applies different AC voltages to the piezoelectric elements 62. . As a result, a standing wave is generated on the inner wall of the silicon tube 61, and traveling waves having different sizes are generated in the fluid in the tube. A composite wave generated by collision of traveling waves of different magnitudes becomes a traveling wave having an elliptical orbit. In this way, the fluid is transported by generating an elliptical motion at an arbitrary point of the fluid.
At this time, the conventional micropump changes the frequency and phase applied to the piezoelectric element, thereby controlling the vibration speed of the piezoelectric element and changing the wavelength of the traveling wave generated in the fluid in the tube to control the flow rate. It was.

International Publication No. 2008/102817 Pamphlet

The above-described conventional micro pump can integrate the flow path and the pump by combining a silicon tube with a ring-type piezoelectric element (PZT element), and can be downsized. Moreover, since this micropump can control the flow rate, it can be applied to, for example, an injection needle for blood collection and drug administration. Thus, the micropump developed by the inventors of the present application is excellent in that it is small in size and capable of minute flow control.

However, the conventional micropump controls the flow velocity by simply changing the frequency and phase applied to the piezoelectric element, but the parameters (for example, AC voltage phase, piezoelectric element installation interval, etc.) are clear. It wasn't a natural thing. For this reason, the conventional micropump has room for further improvement in efficiency, and establishment of a technique for efficiently controlling the speed of the fluid in the narrow tube has been demanded.

The present invention has been made in view of the above situation, and it is an object of the present invention to provide a functional capillary device capable of efficiently controlling the speed of fluid in the capillary and a driving method thereof. .

In the conventional micropump, as described with reference to FIG. 10, traveling waves of different sizes generated in the tube collide by applying different AC voltages to the piezoelectric elements. Therefore, the inventor of the present application pays attention to the fact that the traveling wave generated by the vibration of each piezoelectric element is attenuated by this traveling wave collision, and reduces the amplitude of the traveling wave generated inside the tube body. It has been found that the efficiency of the fluid velocity can be increased by the suppression, and the present invention has been achieved.

That is, in order to solve the above-described problem, the functional thin tube device according to the present invention has a plurality of vibrations that vibrate the tube wall of the tube body inward and outward in the major axis direction of the hollow tube body that transports fluid. An oscillating tube provided with parts spaced apart from each other, and energy supply means for independently supplying the energy for generating traveling waves in the tube by vibrating the plurality of vibrating parts independently, Corresponding to the phase shift when the traveling wave generated by the energy supply means at a certain vibration part reaches the position of the adjacent vibration part in the traveling direction of the fluid, Energy is supplied to the plurality of vibration units so as to generate traveling waves having shifted phases.

In the functional thin tube device configured as described above, a certain vibration unit and a vibration unit located next to the vibration unit in the flow path direction are shifted by a distance from the phase difference of the traveling wave generated in the tube. Has been placed. Therefore, the traveling wave generated by the vibration of a certain vibration part attenuates, but the attenuated traveling wave and the new traveling wave generated by the vibration of the adjacent vibration part have the same phase. Wave attenuation will be compensated.
That is, in the functional thin tube device according to the present invention, each vibration part is arranged at a position shifted by the phase shift of the traveling wave generated in the tube, and therefore, at the position of each vibration part, Attenuation of the traveling wave generated in the tube in the rear is compensated, and the amplitude of the traveling wave traveling in the flow path traveling direction is maintained.

In this functional thin tube device, the vibration-type tube includes m (m is an integer of 2 or more) vibration parts as one unit, the wavelength of the traveling wave is λ, and the vibration adjacent to the vibration part center. When the interval (installation interval) to the center of the part is L and the number of traveling waves generated at the interval is n (n is an integer of 0 or more), the vibration part is L = {(m × n + 1) /M}.times..lamda., And the energy supply means supplies the AC voltage supplied to the other vibration part with reference to the phase of the AC voltage supplied to the vibration part closest to the fluid source of the unit. It is good also as a structure which advances a phase each (360 / m) degree and supplies an alternating voltage.

With this configuration, the functional thin tube device can be provided with a vibrating portion at a position corresponding to the same phase difference for each unit in the vibrating tube, and the vibrating portion is provided at equal intervals in the unit. Can do. In addition, the length of a vibration type tubular body can be ensured by providing a plurality of units.

Further, in this functional thin tube device, the number of the vibration parts in the unit is four, and each vibration part is provided at an interval of L = {(4 × n + 1) / 4} × λ, and the energy supply unit includes: It is good also as a structure which supplies an alternating voltage to each vibration part by shifting a phase of 0 degree, 90 degrees, 180 degrees, and 270 degrees in an order from the vibration part nearest to the source of the fluid of the unit.

With this configuration, the functional thin tube device can be provided with vibrating portions at equal intervals for each unit, and the odd-numbered two vibrating portions are simply inverted (0 °, 180 °). ) And supply an AC voltage. Similarly, the functional thin tube device may simply supply the alternating voltage to the even-numbered two vibrating portions by inverting the phases (90 °, 270 °).

Further, in this functional thin tube device, the energy supply means is configured so that the phase of the AC voltage supplied to the plurality of vibrating parts generating the traveling wave traveling in one direction is reversed by the external switch. It is good also as a structure provided with the traveling wave inversion means to invert so that it may generate | occur | produce in direction.

With such a configuration, the functional thin tube device generates a traveling wave in the opposite direction because the phase of the traveling wave is inverted in the vibration type tubular body. Thereby, the functional thin tube device can reduce the velocity of the fluid flowing in one direction or transport the fluid in the opposite direction.

In order to solve the above-mentioned problem, the present invention separates a plurality of vibration parts that vibrate the tube wall of the tube body inward and outward in the major axis direction of the hollow tube body that transports fluid. A functional tubular device provided with a vibration-type tubular body provided and an energy supply means that independently vibrates the plurality of vibration portions and supplies energy for generating traveling waves in the tubular body. It can also be understood as a driving method of the functional capillary device. At this time, according to the driving method, the traveling wave generated by a certain vibration unit corresponds to the phase shift when the traveling wave reaches the position of the adjacent vibration unit in the fluid traveling direction. It is assumed that energy is sequentially supplied to the plurality of adjacent vibrators so as to generate a traveling wave.

The functional capillary device and the driving method thereof according to the present invention have the following excellent effects.
The functional thin tube device according to the present invention can compensate for the attenuation of the traveling wave by the adjacent vibration parts in the traveling direction in order, and can therefore propagate the traveling wave having a large amplitude in the tubular body. Thereby, the functional thin tube device can efficiently control the speed of the fluid transported in the tube.

Moreover, the functional thin tube device according to the present invention can facilitate the manufacture of the vibration type tubular body by providing the vibrating portions at equal intervals according to the wavelength and the number of waves of the traveling wave generated in the tubular body. .

In addition, the functional thin tube device according to the present invention provides a vibration type tubular body by providing four vibrating parts at equal intervals in one unit according to the wavelength and the number of traveling waves generated in the tubular body. It can be made easier to manufacture. Furthermore, this functional thin tube device only needs to supply an alternating voltage whose phase is inverted to each of the odd-numbered vibration parts or even-numbered vibration parts, and therefore supplies the alternating voltages of different phases to the respective vibration parts. Compared to the case, the energy supply means can be configured simply.

In addition, the functional thin tube device according to the present invention inverts the phase of the AC voltage supplied to the plurality of vibrating portions generating the traveling wave traveling in one direction so that the traveling wave is generated in the opposite direction. By providing the traveling wave reversing means, it becomes possible to control the direction of flow of the fluid or the flow velocity.

In addition, since the driving method of the functional capillary device according to the present invention can compensate the attenuation of the traveling wave by the vibration part in the traveling direction sequentially, the traveling wave having a large amplitude can be propagated in the tubular body. . Accordingly, the method can efficiently control the speed of the fluid transported in the pipe.

(A) is the perspective view which exaggerates the dimension of the vibration type tubular body of the functional thin tube apparatus concerning the embodiment of the present invention, and shows the whole, (b) is the perspective view which expands and shows a part of vibration type tubular body FIG. It is a mimetic diagram showing typically the whole functional thin tube device concerning the embodiment of the present invention. It is a schematic diagram which shows typically the state of the traveling wave in the tubular body of the functional thin tube apparatus which concerns on embodiment of this invention. (A), (b) is explanatory drawing for demonstrating the relationship of the phase of a traveling wave, the phase of an alternating voltage, and the position of a vibration part in the functional thin tube apparatus which concerns on embodiment of this invention. (A), (b), (c) is the phase of the traveling wave, the phase of the alternating voltage, and the position of the vibration part in another embodiment in which the number of vibration parts in the unit of the functional capillary device according to the present invention is changed. It is explanatory drawing for demonstrating the relationship of (interval). It is a schematic diagram which shows typically the structure of the experimental apparatus used in the Example of the functional thin tube apparatus which concerns on this invention. (A), (b), (c) are the examples of the functional thin tube device according to the present invention (Experimental Example 1, Comparative Example 1-1, Comparative Example 1-2). It is the graph which showed the experimental result which changed the position (interval), took the voltage supplied with respect to a vibration part on a horizontal axis, and took the flow velocity in a pipe on the vertical axis. (A), (b) is the experimental result which changed the number of the vibration parts in a unit, and the position (space | interval) of a vibration part in the Example (experimental example 2, comparative example 2) of the functional thin tube apparatus based on this invention. FIG. 5 is a graph in which the horizontal axis represents the voltage supplied to the vibrating portion and the vertical axis represents the flow velocity in the tube. In the example of the functional thin tube device according to the present invention (Experimental Example 3), the experimental results obtained by inverting the phase of the AC voltage are shown, the horizontal axis indicates the voltage supplied to the vibrating part, and the vertical axis indicates the flow velocity in the pipe. FIG. It is a schematic diagram which shows typically the state of the traveling wave in the pipe | tube of the conventional micropump.

Embodiments of the present invention will be described below with reference to the drawings.
[Configuration of functional capillary device]
First, with reference to FIG. 1 and FIG. 2, the structure of the functional thin tube apparatus based on embodiment of this invention is demonstrated. This functional thin tube device generates a traveling wave in the tubular body and transports fluid (liquid, gas) inside the tubular body. Here, the functional thin tube device 1 supplies a vibration-type tube body 2 including a tube body 21 and a plurality of vibration portions 22, and an alternating voltage serving as energy for generating vibration in the vibration portion 22 of the vibration-type tube body 2. Energy supply means 4. The vibration type tube body 2 and the energy supply means 4 are connected by a signal line (cable) 3.

The vibration type tubular body 2 includes a tubular body 21 having a hollow inside, and a plurality of vibration portions 22 that are integrally formed to be separated in the long axis direction of the tubular body 21.
The tube body 21 is hollow inside, and transmits the vibration given by the vibrating portion 22 to the fluid in the tube through the tube wall. Here, a silicon tube is used as an example of the tube body 21.
The tube body 21 may be made of a flexible material such as rubber or resin other than silicon as long as the tube body 21 is hollow and can transmit vibration to the inside. Alternatively, a metal material such as titanium or a titanium alloy may be used.

The vibrating part 22 vibrates the tube wall of the tube body 21 in the inner and outer directions, and is installed separately from the long axis direction of the tube body 21. The position (interval) of the vibration part 22 is determined in advance by the relationship between the waveform of the traveling wave generated inside the tube body 21 and the waveform (phase) of the AC voltage applied to the plurality of vibration parts 22.

Here, the vibration unit 22 is arranged such that a certain vibration unit (for example, the vibration unit 22 ₁ ) and a vibration unit (for example, the vibration unit 22 ₂ ) located adjacent to each other in the flow path traveling direction of the vibration unit are tubes. It is arranged at a position shifted by a distance with respect to the phase difference of the traveling wave generated in the body 21. The position (interval) at which the vibrating portion 22 is provided will be described later in detail.

Further, here, the vibrating section 22 includes a piezoelectric element 22a formed in a ring shape, and metal electrodes 22b and 22c provided on the inner and outer peripheral surfaces of the piezoelectric element 22a.
The piezoelectric element 22a is a piezoelectric body that has been previously polarized in the radial direction and deforms in a ring shape inward and outward when a voltage is applied through the metal electrodes 22b and 22c. The piezoelectric element 22a is, for example, a PZT (lead zirconate titanate) element.

In addition, although the piezoelectric element is illustrated here as a raw material of the vibration part 22, if it is a raw material which vibrates and deform | transforms by energy supply, it will not be limited to a piezoelectric element. For example, if light energy is used as the energy, a polymer material that converts light energy into electrical / mechanical energy, and if magnetic energy is used, a giant magnetostrictive element that converts the magnetic energy into mechanical energy is vibrated. It may be used as a material for the portion 22.

The metal electrodes 22b and 22c apply an AC voltage supplied from the energy supply means 4 to the piezoelectric element 22a. The metal electrodes 22b and 22c are formed of, for example, a metal thin film, and are formed of a platinum, gold, or silver thin film. The metal electrodes 22b and 22c may be made of metal, alloy, or other material as long as it is a conductive material capable of applying a voltage to the piezoelectric element 22a.

Such a vibrating portion 22 can be formed integrally with the tube body 21 by a sputtering deposition method or the like. In addition, the vibration part 22 and the pipe body 21 may be formed separately, and may be integrally formed by bonding with an adhesive, or may be integrally formed by being fused by heat.
The vibration-type tube body 2 may be configured such that the entire tube body 21 is made of a piezoelectric material, a metal electrode is provided on the inner surface of the tube body 21, and a ring-shaped metal electrode is provided at a position where vibration of the outer surface is generated. .

The energy supply means 4 supplies energy for causing a traveling wave to be generated in the tubular body 21 by independently vibrating the plurality of vibrating portions 22. Here, the energy supply means 4 shall supply an alternating voltage to the piezoelectric element 22a of the vibration part 22 via the metal electrodes 22b and 22c. Here, the energy supplied by the energy supply means 4 will be described as an AC voltage. However, if a polymer material having a light energy conversion ability is used for the vibrating portion 22 instead of the piezoelectric element 22a, light energy is supplied. However, if a giant magnetostrictive element is used, magnetic energy can be supplied.

Here, the energy supply unit 4 includes an AC generation unit 41 and a traveling wave inversion unit 42. This energy supply means 4 has a predetermined number of vibrating sections 22 as one unit U, and AC generating sections 41 (41 ₁ , 41 ₂ , 41 ₃ , 41) having the number of channels corresponding to the number of vibrating sections 22 in the unit U. 41 ₄ ). In FIG. 2, an example in which the number of vibration units 22 of one unit U is four is shown, but three may be used, and any integer of 2 or more.

The AC generating unit 41 supplies AC voltages having different phases independently to the vibrating unit 22 in one unit U. Here, the AC voltage supplied by the AC generator 41 is different in phase, and has the same period and amplitude. The AC generator 41 can be configured by a general function generator or amplifier.
The AC voltage V ₁ supplied from the AC generator 41 to the vibrating unit 22 (22 ₁ ) closest to the fluid source in the unit U is expressed by the following equation (1).

Here, A is the amplitude, k (k = 2π / λ; where λ is the wavelength) is the wave number, ω is the angular frequency, and t is the time. That is, the AC voltage V ₁ travels at an angular frequency ω in the x direction (fluid traveling direction) in the tube body 21 by supplying the alternating voltage of the formula (1) to the vibrating portion 22 (piezoelectric element 22a). Wave (traveling wave) can be generated. The AC generator 41 can change the voltage amplitude and the like by an external control knob 4b.

Further, the AC voltages V ₂ , V ₃ , V ₄ supplied to the other vibrating parts 22 (22 ₂ , 22 ₃ , 22 ₄ ) in the unit are as shown in the following equations (2) to (4): The AC voltage V _{1 in the} equation (1) has a waveform in which only the phases (δ ₂ , δ ₃ , δ ₄ ) are shifted.

The phase shift of the AC voltage supplied to each vibration unit 22 generated by the AC generation unit 41 corresponds to the phase shift at the position of each vibration unit 22 of the traveling wave generated inside the tubular body 21. .

As described above, the AC generation unit 41 supplies AC power to each vibration unit 22, and the vibration unit 22 vibrates the wall surface of the tube body 21, thereby causing the fluid particles in the tube body 21 to have an elliptical orbit in one direction. A traveling wave that travels while drawing can be generated.

Further, the AC generator 41 supplies the AC voltage supplied to each vibration part 22 with a phase corresponding to the phase shift at the position of each vibration part 22 of the traveling wave, so that the vibration of the certain vibration part 22 ₁ The phase of the traveling wave generated in the tubular body 21 matches the phase of the traveling wave generated by the vibration of the other vibrating parts 22 ₂ , 22 ₃ , and 22 ₄ , and the attenuation of the traveling wave amplitude is suppressed. Or compensated. The relationship between the phase of the traveling wave and the phase at the position of the vibration unit 22 will be described in detail later.

In addition, the installation interval of each vibration part 22 supplies AC voltage to a certain vibration part 22 (22 ₁ ), and the amount of vibration attenuation by a laser Doppler vibrometer or the like at the position of the adjacent vibration part 22 (22 ₂ ). And at least the ratio of the attenuated vibration amount to the initial vibration amount is set so as not to be equal to or less than a predetermined ratio. For example, the distance from the vibrating portion 22 (22 ₁ ) to the vibrating portion 22 (22 ₂ ) is such that the amplitude of the traveling wave is 50% or more, preferably 70% or more, with respect to the initial vibration amount. It is desirable to do so.

The traveling wave inverting means 42 advances the phase of the AC voltage supplied to the plurality of vibration units 22 that generate traveling waves traveling in one direction in order to switch the direction of traveling waves generated in the tube body 21. It reverses to generate waves in the opposite direction. The traveling wave inversion means 42 inverts the phase of the AC voltage generated by the AC generator 41 when instructed to invert the phase by an instruction from the control knob (external switch) 4b.

Thus, when the phase is inverted by the traveling wave inverting means 42, the AC voltage supplied by the AC generator 41 is, for example, the AC voltage V ₁ expressed by the above equation (1) is (5 ) To the alternating voltage V ₁ shown in the equation.

As shown in the equation (5), the traveling wave generated in the tubular body 21 is reversed by changing the sign of ωt with respect to the equation (1).
As a result, the velocity of the fluid flowing in one direction within the tube body 21 is reduced by the traveling wave in the opposite direction. Furthermore, by continuing to generate the traveling wave, the fluid is transported in the opposite direction.

In addition, as shown in FIG. 1, the functional thin tube device 1 may cover the entire vibration-type tubular body 2 with a cover 23. The energy supply means 4 may be configured in a housing 4d provided with a power switch 4a, control knobs 4b and 4b, a display device 4c, and the like.

[Relationship between traveling wave phase and AC voltage phase and position of vibrating part]
Here, with reference to FIG. 3, the waveform (phase) of the traveling wave generated inside the tube body 21, the phase of the AC voltage supplied by the energy supply means 4 (AC generation unit 41), and the vibration unit 22 An example of the relationship between positions (intervals) will be described.

FIG. 3 partially describes _four vibration portions 22 (22 ₁ , 22 ₂ , 22 ₃ , 22 ₄ ) as one unit of the vibration type tubular body 2. FIG. 3A schematically shows only the traveling wave W ₁ generated in the tubular body 21 by the vibration of the vibrating portion 22 ₁ . FIG. 3B schematically shows a traveling wave W ₁ (solid line) generated by the vibration of the vibration part 22 ₁ and a traveling wave W ₂ (dotted line) generated by the vibration of the vibration part 22 ₂ . .

As shown in FIG. 3A, the amplitude of the traveling wave W ₁ generated by the vibrating portion 22 ₁ is attenuated in the major axis direction due to friction with the tube wall of the tube body 21.

Therefore, as shown in FIG. 3B, the vibration part 22 ₂ is caused by vibration that matches the phase, period, and amplitude of the traveling wave W ₁ generated by the vibration of the vibration part 22 ₁ at the position of the vibration part 22 ₂ . A traveling wave W ₂ is generated. Similarly, in the other vibration parts 22 ₃ and 22 ₄ , traveling waves W ₃ and W ₄ (not shown) that coincide with the phase, period, and amplitude of the traveling wave W ₁ are generated. As a result, the traveling wave W ₁ is synthesized with other traveling waves W ₂ , W ₃ , and W ₄ having the same phase, and as shown in FIG. Wave (synthetic traveling wave) W _ALL is generated, and the flow velocity is increased compared to the case of traveling wave W ₁ alone.

Here, with reference to FIG. 4 (refer to FIGS. 1 and 2 as appropriate), the relationship between the position (interval) of the vibration unit 22 and the phase of the AC voltage supplied by the energy supply unit 4 will be described specifically.
Here, in the functional thin tube device 1, the number of the vibrating portions 22 in one unit of the vibrating tube 2 is m (m is an integer of 2 or more), the wavelength of the traveling wave is λ, the center of the vibrating portion 22 is The interval to the center of another adjacent vibration part 22 is L, and the number of traveling waves generated at the interval (the number of waves of wavelength λ; rounded down after the decimal point) is n (n is an integer of 0 or more). At this time, it is assumed that the interval L between the vibrating portions 22 satisfies the relationship of the following expression (6).

By dividing the wavelength λ of n traveling waves generated between the vibrating parts 22 by the number m of the vibrating parts 22 in the unit as shown in the equation (6), Further, an equal installation interval L of the vibrating parts 22 is obtained.

FIG. 4A shows the case where the distance between the vibrating parts 22 is shorter than the wavelength λ of the traveling wave, that is, the number n of traveling waves generated between the vibrating parts 22 is “0” and one unit of vibration is generated. An example in which the number m of the parts 22 is “4” is shown. In this case, the installation interval L of the vibration part 22 is set to λ / 4 from the above equation (6).

By setting in this way, when the waveform of the AC voltage supplied to the vibrating portion 22 ₁ is sin θ, the phase of the traveling wave at the position of the vibrating portion 22 ₂ is (360 / m) ° from the vibrating portion 22 ₁ . A corresponding shift of 90 ° will occur. That is, the attenuation of the amplitude of the traveling wave can be suppressed by setting the waveform of the AC voltage supplied to the vibration unit 22 ₂ to be cos θ.

FIG. 4B shows that when the interval between the vibrating parts 22 is longer than the wavelength λ of the traveling wave, that is, the number n of traveling waves generated between the vibrating parts of the vibrating part 22 is “1”. In this example, the number m of the vibrating parts 22 of the unit is set to “4”. In this case, the installation interval L of the vibration part 22 is set to 5λ / 4 from the above equation (6).

By setting in this way, similarly to FIG. 4A, when the waveform of the AC voltage supplied to the vibration part 22 ₁ is sin θ, the phase of the traveling wave at the position of the vibration part 22 ₂ is the vibration part 22 _1. Therefore, it is possible to suppress the attenuation of the amplitude of the traveling wave.
In the above description, the number of the vibrating parts 22 in the unit is described as “4”, but this number can be an arbitrary integer of “2” or more.

By setting the number of vibrating parts 22 in the unit to “4”, the AC voltage supplied to the odd-numbered vibrating parts 22 ₁ , 22 ₃ is a signal whose waveform is sin θ and only the phase is inverted. Can do. Similarly, the AC voltage supplied to the even-numbered vibrating portions 22 ₂ and 22 ₄ can be a signal having the same waveform of cos θ and having only the phase inverted.

Therefore, in FIG. 2, the AC generators 41 ₁ , 41 ₂ , 41 ₃ , and 41 ₄ that supply voltages to the respective vibrators 22 are provided. For example, the odd-numbered vibrators 22 ₁ and 22 ₃ The AC generator 41 to be supplied is provided as one, an alternating voltage of sin θ is supplied to _one vibrating unit 22 ₁ , and −sin θ is supplied to the other vibrating unit 22 ₃ via an inverting circuit (not shown). AC voltage may be supplied. Similarly, a single AC generator 41 is supplied to the even-numbered vibrators 22 ₂ and 22 _4, and an AC voltage of cos θ is supplied to one vibrator 22 ₂ , and the other vibrator 22 _{4 is provided.} Alternatively, an AC voltage of −cos θ may be supplied through an inverting circuit (not shown).

Next, with reference to FIG. 5, the relationship between the position (interval) of the vibrating portion 22 and the phase of the AC voltage supplied by the energy supply unit 4 will be described for an example in which the number in the unit is other than “4”. To do. Here, when the interval between the vibrating parts 22 is short, that is, the number n of traveling waves generated between the vibrating parts 22 is set to “0”.

FIG. 5A shows an example in which the number m of vibration units 22 of one unit is “3”. In this case, the installation interval L of the vibration part 22 is set to λ / 3 from the above equation (6).
By setting in this way, when the phase of the waveform of the AC voltage supplied to the vibrating part 22 ₁ is 0 °, the phase of the traveling wave at the position of the vibrating part 22 ₂ is changed from the vibrating part 22 ₁ to (360 / m ) Is shifted by 120 ° corresponding to °. Therefore, in order to suppress the attenuation of the traveling wave, the waveform of the AC voltage supplied to the vibration unit 22 ₂ may be shifted by 120 ° with respect to the phase of the waveform of the AC voltage supplied to the vibration unit 22 _1. . Similarly, it is only necessary to supply an alternating voltage having a waveform whose phase is sequentially shifted by 120 ° in the other vibration units 22.

FIG. 5B shows an example in which the number m of the vibrating units 22 of one unit is “2”. In this case, the installation interval L of the vibration part 22 is set to λ / 2 from the above equation (6).
By setting in this way, when the phase of the waveform of the AC voltage supplied to the vibration part 22 ₁ is 0 ° (sin θ), the phase of the traveling wave at the position of the vibration part 22 ₂ is changed from the vibration part 22 ₁ to ( 360 ° corresponding to 360 / m) °. Therefore, in order to suppress the attenuation of the traveling wave, the waveform of the alternating voltage supplied to vibrating section 22 _2, shifted 180 ° relative to the phase of the waveform of the AC voltage supplied to the vibrating unit 22 _first waveform (-sin) And it is sufficient. Similarly, it is only necessary to supply an alternating voltage having a waveform whose phase is sequentially shifted by 180 ° in the other vibration units 22.

FIG. 5C shows an example in which the number m of the vibrating units 22 of one unit is “6”. In this case, the installation interval L of the vibration part 22 is set to λ / 6 from the above equation (6).
By setting in this way, when the phase of the waveform of the AC voltage supplied to the vibrating part 22 ₁ is 0 °, the phase of the traveling wave at the position of the vibrating part 22 ₂ is changed from the vibrating part 22 ₁ to (360 / m ) Is shifted by 60 ° corresponding to °. Therefore, in order to suppress the attenuation of the traveling wave, the waveform of the AC voltage supplied to the vibration unit 22 ₂ may be shifted by 60 ° with respect to the phase of the waveform of the AC voltage supplied to the vibration unit 22 _1. . Similarly, it is only necessary to supply an alternating voltage having a waveform whose phases are sequentially shifted by 60 ° in the other vibration units 22.

That is, when the m positions (intervals) of the vibrating unit 22 of one unit are determined by the above equation (6), the other is determined based on the phase of the AC voltage supplied to the vibrating unit 22 closest to the fluid source. Therefore, the AC voltage may be supplied to the vibrating unit 22 by advancing the phase by (360 / m) °.

Here, the interval between the vibrating parts 22 in the unit is made equal, and the phase shift supplied to each vibrating part 22 is constant. However, in the present invention, when the vibrating part 22 is set at an arbitrary position, May be supplied to each vibration unit 22 with an AC voltage whose phase is shifted corresponding to the phase shift of the traveling wave at the position. This also can suppress the attenuation of the traveling wave amplitude.
However, considering the ease of manufacturing the functional thin tube device 1, it is desirable to set the vibrating portions 22 at equal intervals.

As described above, the functional thin tube device 1 can suppress or compensate for the attenuation of the amplitude of the traveling wave generated in the tubular body 21 by synthesizing the traveling wave generated by each vibration unit 22. . Thereby, the functional thin tube device 1 can be controlled so that the fluid can be efficiently transported even at a lower voltage.

[Results of functional confirmation of functional capillary device]
Hereinafter, the results of confirming the function of the functional capillary device according to the present invention will be described.
<Experimental example 1>
In this experiment, an experimental apparatus 5 as shown in FIG. 6 is configured, and a fluid is allowed to flow from the water storage tank 51 to the vibration-type tube body 2 of the functional thin tube apparatus 1 through the tube 52 and the measurement apparatus through the tube 53. The function confirmation experiment of the functional thin tube device 1 was performed by measuring the speed of the fluid discharged to 54 (flow rate per unit time).

In this experiment, a silicon tube having an inner diameter of 10 mm, an outer diameter of 12 mm, and a length of 200 mm was used as the tube body 21 of the vibration type tube body 2.
The vibration-type tubular body 2 includes four vibration portions 22, and ring-type PZT elements having an inner diameter of 12.5 mm, an outer diameter of 13.5 mm, and a width of 5 mm are installed at equal intervals as the vibration portion 22. A silver electrode (not shown) was applied to the outer surface and the inner surface of the ring type PZT element. For the ring type PZT element, C-9 (piezoelectric constant d33 718 pm / V) manufactured by Fuji Ceramics Co., Ltd. was used.
Further, pure water was used as a fluid transported inside the tube body 21.

(Wavelength of traveling wave)
First, in the experimental apparatus 5, the wavelength of the traveling wave generated in the tube body 21 was determined by the following procedure.
First, only _one vibration part 22 ₁ is installed in the vibration type tube 2, and pure water is passed through the tube 21 at a steady speed of 1.0 ml / sec.

Then, an AC voltage having a frequency f = 3.0 kHz and a voltage of 80 Vpp is applied to the vibration part 22 ₁ to generate vibration.
Note that the velocity u at which pure water propagates in the tube body 21 by vibration is obtained by the following equation (7).

Here, E is the Young's modulus of the silicon tube that is the tube body 21 (140000 Pa in this experiment), h is the thickness of the silicon tube (1 × 10 ⁻³ m in this experiment), and R is the silicon tube. The outer diameter radius (in this experiment, 5 × 10 ⁻³ m) and ρ is the density of pure water (in this experiment, 1000 kg / m ³ ).
Then, the wavelength (λ) of the traveling wave is obtained by the following equation (8).

Here, u is a propagation velocity obtained by measurement (or calculation in equation (7)), and f is a frequency (3.0 kHz in this experiment).
Thus, the wavelength λ of the traveling wave was obtained in advance as 1.25 mm.

(Spacing between vibration parts)
And the installation interval (from the center of the ring-type PZT element to the center) of the other vibration parts 22 ₂ , 22 ₃ , and 22 ₄ installed rearward with respect to the direction of the flow of pure water in the tube 21 of the vibration part 22 ₁ L) is determined by the above equation (6) ({(m × n + 1) / m} × λ).

In this experiment, the number m of the vibrating parts 22 is “4”, the number n of traveling waves generated between the vibrating parts 22 is “8”, and the wavelength λ of the traveling wave previously obtained is “1.25”. Therefore, the installation interval L of the vibration part 22 was determined as 10.3 mm according to the equation (6).
Then, the vibration parts 22 ₁ , 22 ₂ , 22 ₃ , and 22 ₄ were adjusted and installed so that the installation interval from the center to the center was 10.3 mm.

(experimental method)
In this experiment, with the vibration unit 22 installed on the tube body 21 as described above, pure water is passed through the tube body 21 at a steady speed of 1.0 ml / sec, and an AC voltage is applied to the vibration unit 22. Thus, the flow rate of pure water was measured. This measurement was performed for 20 seconds at a time, and the average value was obtained by repeating the measurement five times.

In this experiment, the frequency of the AC voltage generated by the AC generator 41 of the energy supply means 4 is 3.0 kHz, and the voltage is 5 Vpp, 7.5 Vpp, 10 Vpp, 12. Five conditions (experiment numbers (1) to (5)) of 5 Vpp and 15 Vpp were used. Further, the energy supply means 4 shifts the phase of each vibration part 22 so that the vibration parts 22 ₁ , 22 ₂ , 22 ₃ , and 22 ₄ satisfy (360 / m) ° [m is the number of vibration parts]. An alternating voltage having a waveform shifted by 90 ° (sin θ, cos θ, −sin θ, −cos θ) was supplied.

FIG. 7A shows the result of the experiment conducted under the conditions of [Table 1]. FIG. 7A shows the AC voltage (AC Voltage [Vpp]) applied to the horizontal axis and the flow velocity (Flow velocity [ml / s]) on the vertical axis. Moreover, the plot in the figure shows the average value of 5 times, and the vertical line added to the plot shows the standard deviation (variation) of 5 times.
As can be seen from FIG. 7A, it was confirmed that the flow rate increased linearly by increasing the voltage with respect to the initial flow rate of pure water (1.0 ml / s).

<Comparative Example 1-1>
Supplying Here, for comparison with Experimental Example 1, the vibrating unit 22 _1, 22 _2, 22 _3, the installation position of 22 ₄ are the same, the vibrating unit 22 _1, 22 _2, 22 _3, 22 ₄ Since the phase shift of the AC voltage does not satisfy (360 / m) ° [m is the number of vibrating portions], the phase of the traveling wave generated by each vibrating portion 22 is a predetermined phase shift of the traveling wave. An experiment was conducted for a case that did not fit.

In Comparative Example 1-1, basically, only the phase of the AC voltage supplied to the vibrating portions 22 ₁ , 22 ₂ , 22 ₃ , and 22 ₄ is changed with the same configuration and the same conditions as in Experimental Example 1. Yes. That is, in Comparative Example 1-1, as shown in [Table 2], the energy supply means 4 is moved to the vibrating portions 22 ₁ , 22 ₂ , 22 ₃ , and 22 ₄ at (360 / m) ° [m is the vibrating portion. AC voltage having a waveform (sin θ, cos θ, sin θ, cos θ) that does not satisfy the above condition is supplied.

FIG. 7B shows the result of a comparative experiment performed under the conditions of [Table 2]. FIG. 7B shows the AC voltage [Vpp] applied on the horizontal axis and the flow rate [ml / s] on the vertical axis.
As can be seen from FIG. 7B, by increasing the voltage with respect to the initial flow rate of pure water (1.0 ml / s), the flow rate gradually increases but the value is small. It was found that the slope was gentle compared to (a), the flow rate could not be increased efficiently with respect to the voltage, and the control efficiency was low.

<Comparative Example 1-2>
Further, for comparison with Experimental Example 1, the phase shift of the AC voltage supplied to the vibrating parts 22 ₁ , 22 ₂ , 22 ₃ , and 22 ₄ satisfies (360 / m) ° [m is the number of vibrating parts]. Even in this case, the installation interval of the vibrating parts 22 ₁ , 22 ₂ , 22 ₃ , 22 ₄ does not satisfy the condition of {(m × n + 1) / m} × λ (the above formula (6)). An experiment was conducted in the case where the phase of the traveling wave generated by each vibration unit 22 did not match the predetermined phase shift of the traveling wave.

In Comparative Example 1-2, basically, the same configuration and the same conditions as in Experimental Example 1 were used, and only the installation interval of each vibrating portion 22 was changed to 12.0 mm. This installation interval value of 12.0 mm is a value between n = 10 and n = 11 in {(m × n + 1) / m} × λ.

FIG. 7C shows the result of supplying an alternating voltage having the same phase as in [Table 1] to the vibrating portions 22 ₁ , 22 ₂ , 22 ₃ , and 22 ₄ in this configuration. FIG. 7C shows the AC voltage [Vpp] applied on the horizontal axis and the flow rate [ml / s] on the vertical axis.
As can be seen from FIG. 7 (c), the flow rate is increased by increasing the voltage with respect to the initial flow rate (1.0 ml / s) of pure water, but the value is still small, and FIG. Compared to 7 (a), the slope was gentler, and the flow velocity could not be increased efficiently with respect to voltage.

As can be seen from the experimental results of FIGS. 7A to 7C, the phase of the AC voltage supplied to the vibration unit 22 and the installation interval of the vibration unit 22 are set under conditions that match the phase of the traveling wave. It can be seen that the flow rate is greatly improved.

That is, when FIG. 7A is compared with FIGS. 7B and 7C, the present invention can obtain higher fluidity by supplying a high voltage to the vibrating portion 22. Moreover, even if it is a case where a low voltage is supplied to the vibration part 22, this invention has acquired the high fluidity | liquidity.
As described above, the present invention can efficiently transport a fluid even at a low voltage, and thus can be applied to a micropump that needs to be driven at a low voltage.

<Experimental example 2>
Next, as Experimental Example 2, one unit of the vibration type tubular body 2 was configured by _three vibration portions 22 (22 ₁ , 22 ₂ , 22 ₃ ) and an experiment was performed.
That is, in Experiment 2, the experiment is basically performed with the same configuration and the same conditions as in Experiment 1, but the number of vibration units 22 installed in one unit is changed from four to three. Went. The measuring device is the same as the experimental device 5 described in FIG.

At this time, in Experimental Example 2, the installation interval (installation interval from the center of the ring-type PZT element) L of the vibrating portions 22 ₁ , 22 ₂ , and 22 ₃ is expressed by the above equation (6) ({(m × n + 1) / M} × λ) and was 10.4 mm. In Experimental Example 2, n and λ in Equation (6) are “8” and “1.25” as in Experimental Example 1, and only m is “3”, which is different from Experimental Example 1. .

In Experimental Example 2, as shown in [Table 3], the AC generating unit 41 of the energy supply means 4 is moved to (360 / m) ° [m is the vibrating unit] in the vibrating units 22 ₁ , 22 ₂ , and 22 _3. The AC voltage having a waveform whose phase is shifted by 120 ° is supplied to each of the vibrating sections 22 so as to satisfy the above. Other conditions are the same as in Experimental Example 1.

FIG. 8A shows the result of the experiment conducted under the conditions of [Table 3].
As can be seen from FIG. 8A, it was confirmed that the flow rate increased linearly by increasing the voltage with respect to the initial flow rate of pure water (1.0 ml / s).

<Comparative Example 2>
Here, for comparison with Experimental Example 2, the phase shift of the AC voltage supplied to the vibrating parts 22 ₁ , 22 ₂ , and 22 ₃ satisfies (360 / m) ° [m is the number of vibrating parts]. Even if it exists, each installation of the vibration parts 22 ₁ , 22 ₂ , and 22 ₃ does not satisfy the condition of {(m × n + 1) / m} × λ (the above expression (6)). An experiment was conducted in the case where the phase of the traveling wave to be generated did not match a predetermined phase shift of the traveling wave.
In Comparative Example 2, basically, the same configuration and the same conditions as in Experimental Example 2 were used, and only the installation interval of the vibrating portions 22 was changed to 12.0 mm.

FIG. 8B shows the result of supplying an alternating voltage having the same phase as in [Table 3] to the vibrating portions 22 ₁ , 22 ₂ , and 22 ₃ in this configuration.
As can be seen from FIG. 8 (b), the flow rate is increased by increasing the voltage with respect to the initial flow rate (1.0 ml / s) of pure water, but the value is still small. The slope was gentle compared to 8 (a), and the flow rate could not be increased efficiently with respect to voltage.

In other words, the functional thin tube device 1 matches the phase of the AC voltage supplied to each vibrating unit 22 with the phase of the traveling wave in the tube 21 even when the number of vibrating units 22 in the unit is three. By doing so, the fluid can be efficiently transported even at a lower voltage.

<Experimental example 3>
Next, as Experimental Example 3, an experiment was performed to reverse the phase of the AC voltage supplied to the vibrating units 22 ₁ , 22 ₂ , 22 ₃ , and 22 ₄ with the same configuration as that of Experimental Example 1.
That is, in Experimental Example 3, as in Experimental Example 1, the installation interval of the vibrating parts 22 was set to 10.3 mm satisfying the above expression (6). Further, in Experimental Example 3, as shown in [Table 4], the energy supply unit 4 causes the traveling wave inversion unit 42 to invert the phase of the AC voltage generated by the AC generation unit 41, thereby oscillating the unit 22 _1. , 22 ₂ , 22 ₃ , and 22 ₄ were supplied with AC voltages having waveforms (−sin θ, −cos θ, sin θ, cos θ) whose phases were inverted from those of the AC voltage used in Experimental Example 1. Other conditions are the same as in Experimental Example 1.

The results of experiments conducted under the conditions shown in Table 4 are shown in FIG.
As can be seen from FIG. 9, it was confirmed that when the voltage was increased with respect to the initial flow rate of pure water (1.0 ml / s), the flow rate decreased linearly.

As described above, the functional thin tube device 1 sets the position of the vibration unit 22 and the phase of the AC voltage supplied to each vibration unit 22 so as to match the phase of the traveling wave generated in the fluid in the tube body 21. By adjusting, the fluid can be efficiently transported with respect to the applied AC voltage.
Moreover, since the functional thin tube device 1 can efficiently transport a fluid even at a low voltage, it can be realized as a micropump that is small and requires low-voltage driving.
Furthermore, the functional thin tube device 1 can increase or decrease the flow velocity by simply inverting the phase of the AC voltage to be applied, and can easily control the fluid velocity.

DESCRIPTION OF SYMBOLS 1 Functional thin tube apparatus 2 Vibrating-type tubular body 21 Tubing body 22 Vibrating part 22a Piezoelectric element 22b Metal electrode 22c Metal electrode 23 Cover 3 Signal line (cable)
4 Energy supply means 41 AC generator 42 Traveling wave reversing means 4a Power switch 4b Control knob (external switch)
4c display device 4d housing 5 experimental device 51 water storage tank 52 tube 53 tube 54 measuring device U unit

Claims (5)

1. A vibration-type tube body provided with a plurality of vibration parts spaced apart from each other in the major axis direction of a hollow tube body that transports fluid in the long axis direction, and the plurality of vibrations An energy supply means for supplying energy for independently vibrating parts to generate traveling waves in the tubular body,
   The energy supply means includes
   Corresponding to a phase shift when a traveling wave generated by a certain vibration part reaches the position of the adjacent vibration part in the traveling direction of the fluid, the progression of the phase shifted by the shift in the adjacent vibration part A functional capillary device, wherein energy is supplied to the plurality of vibrating portions so as to generate a wave.
2. In the functional capillary device according to claim 1,
   The vibrating tube is
   m (m is an integer greater than or equal to 2) of the above-mentioned vibrating parts are set as one unit, the wavelength of the traveling wave is λ, the distance from the center of the vibrating part to the center of the vibrating part is L, and the traveling wave generated at the interval is When the number of waves is n (n is an integer greater than or equal to 0), the vibrating portions are provided at intervals of L = {(m × n + 1) / m} × λ,
   The energy supply means includes
   Based on the phase of the alternating voltage supplied to the vibrating part closest to the fluid source of the unit as a reference, the phase of the alternating voltage supplied to the other vibrating part is advanced by (360 / m) °, respectively. A functional capillary device characterized by supplying.
3. In the functional capillary device according to claim 1,
   The number of the vibration parts in the unit is four, and each vibration part is provided at an interval of L = {(4 × n + 1) / 4} × λ.
   The energy supply means includes
   A functional capillary device that supplies an alternating voltage to each of the oscillating units by sequentially shifting the phase by 0 °, 90 °, 180 °, and 270 ° from the oscillating unit closest to the fluid source of the unit.
4. In the functional thin tube device according to any one of claims 1 to 3,
   The energy supply means includes
   Traveling wave reversing means for reversing the phase of the AC voltage supplied to the plurality of vibrating parts generating traveling waves traveling in one direction by an external switch so as to generate the traveling waves in the opposite direction. A functional capillary device characterized by comprising.
5. A vibration-type tube body provided with a plurality of vibration parts spaced apart from each other in the major axis direction of a hollow tube body that transports fluid in the long axis direction, and the plurality of vibrations Using a functional thin tube device provided with energy supply means for supplying energy for independently generating vibrations to generate traveling waves in the tubular body,
   Corresponding to a phase shift when a traveling wave generated in a certain vibrating section reaches a position of an adjacent vibrating section in the traveling direction of the fluid, a traveling wave having a phase shifted by the shift is generated. A driving method of a functional capillary device, wherein energy is sequentially supplied to a plurality of adjacent vibration units.

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