JP5743265B2 - Atomizing spray equipment - Google Patents

Description

The present invention relates to an atomizing spray device that sprays liquids such as drugs, cosmetic liquids, fragrances, vaccines, and high-concentration electrolytes from a fine nozzle using ultrasonic vibration.

A device that vibrates a nozzle plate having a large number of fine nozzles with a piezoelectric vibrator and sprays the liquid supplied to the nozzle plate from the nozzle, or an ultrasonic vibrator close to the nozzle plate having a large number of fine nozzles In recent years, the device that sprays the liquid supplied from the nozzle through a nozzle is widely applied to medical nebulizers (humidifiers), humidifiers, aroma diffusers, and nebulizers for moisturizing cosmetic liquids. Has been.

As these atomization spray devices, a device for intermittently diffusing fine particles sprayed from the nozzle (see Patent Document 1), or a vibrator for power saving or power limitation to the vibrator. Devices for intermittent operation (see Patent Document 2 and Patent Document 3) are disclosed.

On the other hand, regarding the technology for ejecting high-viscosity liquid as droplets from a nozzle, the viscosity of the high-viscosity liquid is controlled by a technology (see Patent Document 4) that gives a large shearing force necessary for shearing droplets for ejection, or temperature. A technique (see Patent Document 5) that makes it easy to discharge from a nozzle by reducing the pressure is disclosed.

JP 2002-536173 A JP 2000-271517 A JP 2005-511275 Gazette JP 2010-142737 A JP 2003-220702 A

However, (1) it is difficult to continuously atomize and disperse high-viscosity solutions, and (2) it is difficult to absorb and diffuse high-viscosity dispersed droplets on the receiving side.
First, (1) As a problem of the atomization method, the atomization performance exhibited by the atomization spray device is limited by the viscosity due to the physical properties of the atomization liquid, and a high-viscosity liquid exceeding 10 mPa · s (10 cps). For example, Patent Document 1 discloses that atomization is difficult.
However, in medicines, cosmetic liquids, aroma liquids and the like, atomization of high-viscosity liquids exceeding 10 mPa · s (10 cps) is particularly expected, and there is a problem that this expectation cannot be met.
(2) A problem in the absorption of atomized droplets is, for example, that it is difficult to inject electrolyte into an EDLC container in small EDLC manufacturing. Ultra-compact EDLC requires MSD (surface mount) function and requires solder reflow conditions (260 ° C * 10 seconds), so ionic liquids such as EMIBF4 (Ethyle, Methyle, Imidazolium tetra Fuluoro Borate) have high viscosity. The surface tension is large, and even if the electrolyte is dropped, it does not diffuse or penetrate into the electrode mixture, so the temperature of the droplet environment is increased or the pressure is reduced and the electrolyte is supplied. Thus, a technique for permeating and diffusing such a high-viscosity ionic liquid into the electrode mixture at high speed has been expected.

However, with the technique using a large shear force, which is a conventional attempt in atomizing a high-viscosity liquid, the liquid supply structure of the atomization spray device is complicated, the power consumption is increased, or the variation in droplet size due to the strong shear force is increased. There were issues such as.
Further, in the technology for reducing the viscosity of the liquid and facilitating the discharge, there is a problem that the range of selection of the chemical solution that can be used in the field of medical nebulizers is narrowed because chemical modification and decomposition of the liquid occur due to heat.

The present invention pays attention to the above-mentioned problems, and the liquid supply structure and the atomization spray structure remain simple, and even in a high-viscosity solution that is difficult to atomize, the liquid is not modified or decomposed. An object of the present invention is to provide an atomizing and spraying apparatus that is practically extremely useful and capable of atomizing and spraying high viscosity liquids.

According to the first aspect of the present invention, a nozzle plate having a large number of nozzles and supplied with viscous liquid, a vibrator that vibrates the nozzle plate or the viscous liquid, and vibration and stop of the vibrator are intermittently provided. It possesses an electrical signal generating means for repeating the spray outlet side of the plurality of nozzles, wherein the continuous atomization spraying of viscous liquid sump of the viscous liquid to a spray outlet surface of the nozzle plate adjacent occur a atomizing spray apparatus is closed, the spray of the plurality of nozzles spraying outlet of the nozzle plate adjacent said viscous liquid puddle occurs in the spray outlet surface of the nozzle plate by the continuous atomization spray Before the outlet side is blocked, the vibration of the vibrator is stopped by the electric signal generating means , and after the stop, the intermittent operation is performed to vibrate the vibrator again .

The liquid is ejected from the nozzle by ultrasonic vibration to form a droplet, and this droplet is generated every time the vibrator is vibrated, and becomes a nebulized spray by continuously ejecting a large number of droplets. If the viscosity of the liquid increases, the vibration energy does not increase and the liquid does not leave the nozzle plate as droplets.
The inventors of the present invention have a high-viscosity liquid exceeding 10 mPa · s (10 cps), and even if vibration energy is increased, the liquid tends to be pulled back to the nozzle plate before being separated as droplets and adheres to the nozzle plate. It was confirmed that the liquid gradually gathered and blocked the nozzles, preventing the generation of droplets.

Results of analysis of this phenomenon, spray outlet side of the plurality of nozzles adjacent that Ru covered wet viscous liquid, was investigated to be a cause of impossible atomize high viscosity liquid.
For this reason, as described above, as the timing for intermittently stopping the vibration of the vibrator, the vibration is stopped before the spray outlet side of many adjacent nozzles is wet-covered with the viscous liquid due to the vibration.・ Even with high viscosity liquids exceeding s (10 cps), atomization spray can be performed.

The inventors have also confirmed that when the amount of liquid adhering to the nozzle is small, the liquid adhering to the nozzle is absorbed and integrated with the liquid in the nozzle by surface tension when the nozzle is stationary. It was found that the generation of droplets due to the next vibration can be resumed by this absorption integration during the stop after the vibration. It has also been found that this phenomenon of absorption integration requires more time for the same amount of the adhering liquid, so that the higher the viscosity, the longer the time required.

The invention described in claim 2 has a detecting means for detecting the temperature of the viscous liquid, and a determining means for determining the length of the electric signal in accordance with the detected temperature. The amount of the viscous liquid to be atomized and sprayed is controlled.

The invention described in claim 3 is such that the viscous liquid has a high viscosity of 10 to 40 mPa · s at 20 ° C.

According to a fourth aspect of the present invention, the viscosity of the viscous liquid is set to 10 mPa · s or more and the vibration time is set to 20 ms or less.

According to the fifth aspect of the present invention, the viscosity of the viscous liquid is set to 30 mPa · s or more and the vibration time is set to 10 ms or less.

In a sixth aspect of the invention, the distance between adjacent nozzles is 150 μm or more.

According to the atomizing spray device of the first aspect of the present invention, the high-viscosity liquid prevents the nozzle from being clogged and continuously atomizes and sprays the liquid without generating a droplet from the nozzle. In addition, the liquid supply structure and the atomization spray structure can be atomized and sprayed not only with a low viscosity but also with a particularly high viscosity liquid without any modification or decomposition of the liquid, with a simple structure. An excellent effect can be obtained.

According to the atomizing spray device of the second aspect of the present invention, the vibration and stopping time of the vibrator can be accurately controlled according to the liquid clay, and the atomizing spray can be performed even with a high viscosity liquid. An effect can be obtained.

According to the atomization spray apparatus according to claim 3 of the present invention, it is possible to obtain a viscous liquid having a high viscosity of 10 to 40 mPa · s at 20 ° C., which could not be obtained by the prior art. An excellent effect can be obtained.

According to the atomizing and spraying apparatus according to claims 4 and 5 of the present invention, the higher the viscosity of the liquid, the less likely it becomes droplets, so that the liquid tends to adhere to the nozzle plate. As the viscosity increases, the vibration time is shortened as the viscosity becomes higher. Therefore, it is possible to obtain an excellent effect that it is possible to prevent the high-viscosity liquid from being unable to be atomized and sprayed.

According to the atomizing spray device of the sixth aspect of the present invention, if the distance between the nozzles is too short, it is possible to prevent the nozzles on the spray outlet side from being connected by a liquid film and being unable to atomize and spray. An excellent effect can be obtained.

It is sectional drawing of the atomization spray apparatus which shows 1st embodiment of this invention. It is a figure which shows the impedance characteristic of the vibrator | oscillator used for 1st embodiment of this invention. (A), (B), (C) is a figure which shows the pulse waveform in 1st embodiment of this invention. It is explanatory drawing which shows the atomization spray operation | movement in 1st embodiment of this invention. It is expansion explanatory drawing which shows the operation | movement from which the atomization spray in 1st embodiment of this invention differs. It is a figure which shows the pulse application pattern in 1st embodiment of this invention. It is sectional drawing of the atomization spray apparatus which shows 2nd embodiment of this invention. It is a figure which shows the pulse application pattern in 3rd embodiment of this invention. It is sectional drawing of the atomization spray apparatus which shows 5th embodiment of this invention. In the characteristic diagram in the sixth embodiment of the present invention, (A) is time-nozzle temperature, (B) is temperature-viscosity, and (C) is discharge time-discharge amount. It is a figure which shows the pulse application pattern in 6th embodiment of this invention.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.
(First embodiment)
A nozzle type atomizing spray apparatus 10 according to a preferred first embodiment of the present invention is shown in FIG. The nozzle plate 11 has a large number of nozzles 12 with an arrangement pitch of 200 μm and a diameter of 12 μm (the range of the diameter is 1 to 100 μm) manufactured by electroforming technology, and is bonded to the piezoelectric vibrator 13. In the container 20 provided on one side of the nozzle plate 11, a viscous liquid 21 which is a moisturizing cosmetic liquid having a high viscosity of 10 to 40 mPa · s (10 to 40 cps) at 20 ° C. which is atomized and sprayed. It is filled with the nozzle 12 in contact. The piezoelectric vibrator 13 in this state has a resonance frequency of about 98 kHz as shown in FIG. 2 and is connected to a pulse generation drive circuit 14 which is an electric signal generation means.

The voltage pulse for driving the piezoelectric vibrator 13 is a sine wave shown in FIG. 3A, and has a frequency of 100 kHz and a voltage amplitude of about 40V. This voltage pulse is applied to the piezoelectric vibrator 13 repeatedly in units of a pulse application pattern in which the pulse pulse is continuously oscillated at 400 pulses for Ton = 3 ms and then stopped for a time equivalent to 1000 pulses Toff = 10 ms. As shown in FIG. 3B, the Toff in the electric signal also realizes the following action by reducing the amplitude voltage to a voltage that does not cause the piezoelectric element to substantially vibrate. Further, as shown by Toff in FIG. 3C, the following operation can be similarly realized by modulating the resonance frequency at Ton to a frequency that does not cause substantial vibration.

Due to the vibration caused by the voltage pulse of the piezoelectric vibrator 13, a droplet 31 is generated from the nozzle 12 as shown in FIG. 4, and the viscous liquid 21 starts to atomize 32. During the application of driving pulses of 400 pulses, FIG. 5 (A), the spray outlet 15 of the nozzle 12A becomes liquid reservoir 33 without becoming droplets on the surface of some of the nozzles 12 A Thereafter, the liquid reservoir 33 grows with increasing capacity each time the nozzle vibrates. When the driving pulse of the piezoelectric vibrator 13 is stopped after the driving pulse of 400 pulses, as shown in FIG. 5B, the liquid reservoir 33 collected on the spray outlet side 15 of the nozzle 12A is the cosmetic liquid 21 on the back surface of the nozzle 12A. Is sucked by the surface tension, and returns to the state before the start of vibration as shown in FIG.

In the first embodiment, when the number of continuous oscillation pulses is 5000 pulses or more (Ton = 50 ms), the liquid reservoir 33 becomes too large as shown in FIG. The large area was blocked, no droplets were generated, and the atomization spray stopped with a pulse application pattern of several units.

Further, when the stop time Toff following the 300 drive pulses is set to less than 3 ms corresponding to 300 pulses, the next drive pulse remains incompletely sucked in the liquid reservoir 33 as shown by a broken line in FIG. Application occurred, the liquid reservoir 33 grew, and the atomization spray stopped with a pulse application pattern of several units.

FIG. 6 shows the result of an experiment in which the level combination of Ton and Toff was performed with respect to the pulse application pattern in the viscous liquid 21 described above. In FIG. 6, the area A is an atomized spray impossible, the area C is a continuous atomized spray, and the area B is an unstable atomized spray area. In the present embodiment, Ton is 20 ms (2000 pulses) or less at the maximum, and Toff needs to be longer as Ton is longer in the time range.

(Second embodiment)
FIG. 7 shows the second embodiment. The nozzle plate 12 having the nozzles 11 is disposed so as to face a separate body from the piezoelectric vibrator 14, and is disposed between the nozzle plate 12 and the end face of the piezoelectric vibrator 14. In this apparatus, the viscous liquid 21 is supplied into a gap of several tens of μm to several hundreds of μm, and the cosmetic liquid 21 vibrates due to the vibration of the end face of the piezoelectric vibrator 14. Also in this apparatus, the mechanism in which the cosmetic liquid 21 and the nozzle 11 relatively vibrate is the same as that in the first embodiment described above, and the operation is the same.

(Third embodiment)
The same experiment as that of the first embodiment was performed in an apparatus in which the surface of the spray outlet 15 of the nozzle 11 in the first embodiment described above was subjected to fluorine-based water repellent (oil repellent) treatment. Note that the contact angle of the viscous liquid 21 in the case of the untreated water repellent of the first embodiment was about 80 degrees, whereas the viscous liquid 21 on the spray outlet side 15 surface of the nozzle 11 in the third embodiment was The contact angle is about 100 degrees.

FIG. 8 shows experimental results obtained by combining the levels of Ton and Toff in the third embodiment in the same manner as in the first embodiment. Compared with the first embodiment, Ton of C region where stable atomization spraying is possible is longer and Toff is shorter. By performing the water repellent treatment in this way, a pulse application pattern that can increase the number of continuous pulses and shorten the stop can be realized. Since Ton extended to a maximum of 50 ms, it was found that a higher viscosity liquid can be atomized and sprayed by combining intermittent driving of a pulse application pattern composed of Ton and Toff and water repellent treatment.

(Fourth embodiment)
The same experiment as that of the first embodiment was performed in each device in which the arrangement pitch of the nozzles 12 in the first embodiment described above was varied from 100 μm to 300 μm. Table 1 shows Ton and Toff level combinations in the fourth embodiment together with the first embodiment.

From the results shown in Table 1, the Ton time can be extended if the arrangement pitch of the nozzles 12 is long, but the arrangement pitch of the nozzles 12 does not affect the amount of Ton that is short. This is because the liquid reservoir 33 shown in FIG. 5A is easily connected between the adjacent nozzles 12 if the arrangement pitch of the nozzles 12 is short, and if connected, the liquid reservoir 33 as shown in FIG. It was analyzed that the nozzle 12A remained blocked by the liquid in the nozzle 12A. For this reason, if it is a high-viscosity liquid of 10 mPa · s (10 cps) or more, which has been difficult in the past, a nozzle arrangement pitch of at least 150 μm is desirable for stable atomization spray, and less than Ton 50 ms, preferably Ton = 20 ms or less It turned out to be necessary.

(Fourth embodiment)
In the first embodiment described above, since the viscosity of the viscous liquid 21 was 40 mPa · s (40 csp), an experiment was conducted to examine a pulse application pattern capable of atomizing spraying in liquids having different viscosities. The results for viscosities of 5 mPa · s (5 cps), which is conventionally said to be atomizable, viscosity of 10 mPa · s (10 cps), which is said to be difficult, and 40 mPa · s (40 csp), which are said to be difficult, are as shown in Table 2. .

As shown in Table 2, at 10 mPa · s (10 cps), continuous atomization was difficult with a continuous pulse without Toff, but continuous atomization was possible at Ton = 50 ms or less. From Table 2, the pulse application pattern greatly depends on the viscosity, and the duty ratio of Ton / (Ton + Toff) at 10 mPa · s (10 cps) or more, which is difficult to spray continuously, was higher as Ton was shorter. That is, the higher the viscosity is, the more difficult it is for continuous spraying, and the pulse application with a short Ton pattern increases the spray rate and improves the efficiency. In particular, at about 30 mPa · s (30 cps) or more, Ton = 10 ms or less, and practically, Ton = 5 ms or less, which is a region where a duty of 30% or more can be obtained, is desirable. Further, it was found that when the viscosity of the cosmetic liquid 21 is 20 mPa · s (20 cps), atomization spraying is possible with Ton = 20 ms or less, and particularly when Ton = 10 ms or less, the duty ratio can be increased to about 50% or more. .

(Fifth embodiment)
FIG. 9 shows a fifth embodiment of the atomizing spray device. This device is a chemical solution injection device, and the viscous liquid 41 to be atomized and sprayed based on the atomization spray device of the first embodiment is a medical solution for medical use, and the nozzle plate 42 has one nozzle 44 in the center. It is bonded to the vibrator 43. This vibrator is repeatedly vibrated and stopped intermittently as in the first embodiment by a drive circuit 52 which is an electric signal generating means. A medical capsule 50 is disposed below the nozzle 44, and a liquid droplet 46 discharged from the nozzle 44 is injected into the capsule 50 having a capacity of 5 microliters (μL). The liquid droplets 46 are ejected as if they were liquid columns while the nozzle plate 42 vibrates, and the liquid droplets are interrupted while the vibration is stopped.

In the medical field, it is required that the accuracy of the chemical amount of one capsule be suppressed to about ± 10%, but the viscosity changes depending on the temperature of the chemical solution, which is accompanied by a change in the discharge amount per time. In the fifth embodiment, a resistance temperature sensor 45 which is a temperature detecting means for viscous liquid is disposed in the vicinity of the nozzle plate 42, and this temperature sensor resistance is read from the AD conversion input terminal of the microcomputer 51, and is stored in the ROM 53 referred to by the microcomputer 51. It is composed of a determining means that performs calculation with reference to the conversion table of the discharge rate corresponding to the chemical temperature stored in the table, and sequentially determines the discharge time. The determined discharge time is set as the length of the electric signal. The vibrator is vibrated by the drive circuit 52 (electric signal generating means), and as a result, the atomized spray amount of the viscous liquid 41 is controlled.

In the apparatus of the sixth embodiment, as shown in FIG. 10A, the temperature near the piezoelectric vibrator 43 is changed from the room temperature or the chemical temperature at the beginning of operation to the vicinity of the piezoelectric vibrator 43 along with the operation time of the apparatus (drive of the piezoelectric vibrator 43). Later, it rises to about 35 ° C. and saturates. As shown in the fifth embodiment, there are areas of maximum Ton (maximum number of pulses) and minimum Toff that can be discharged or stably discharged according to the viscosity of the chemical solution, and when there is a change in viscosity, the highest to be driven Industrially, a pulse application pattern design based on viscosity-stable ejection is desirable. That is, it is possible to realize a simple device by selecting a stable pulse application pattern at a minimum temperature at which the chemical liquid has a relatively high viscosity and determining the chemical injection time according to the temperature in the pulse application pattern. Here, the chemical injection time refers to the time T1 of the electric signal shown in FIG. 11, and the electric signal included in the time T1 is composed of repetition of Ton and Toff shown in FIG. 3 in the first embodiment described above. ing.

Therefore, referring to Table 2 based on the viscosity of 35 cps at room temperature in the viscosity curve with respect to the temperature of the chemical solution shown in FIG. 11 (B), a pulse application pattern with Ton = 5 ms and Toff = 10 ms is selected. It is an apparatus that applies the voltage pulse of the selected pattern to the piezoelectric vibrator 43 by creating the conversion table for the time T1 corresponding to the temperature so that this pattern is repeatedly applied for a time corresponding to the chemical temperature. Simplified cost performance is optimal. FIG. 10C shows the discharge speed when the pulse application pattern is 25 to 35 mPa · s (25 to 35 cps) corresponding to a temperature range of 25 to 40 ° C. The discharge time (chemical solution injection time) control is determined by tabulating the discharge time of 5 μL at each temperature. As a result, the chemical solution injection time T1 can be performed at a maximum of 170 ms per capsule, and continuous capsule injection is possible with an injection tact time T2 of 220 ms. In addition, if the nozzle plate 42 is subjected to water repellent treatment as in the third embodiment, it is possible to perform a chemical solution injection operation in a shorter time.

The apparatus of the sixth embodiment can be applied to electrolyte injection into a small EDLC described in the problem to be solved by the invention. In this application, the capsule 50 is a small EDLC container and contains an electrode mixture having a thickness of 400 to 700 μm inside. Since the electrolytic solution EMIBF4 is a viscous liquid having a viscosity of 30 to 35 mPa · s (30 to 35 cps), it is discharged from the nozzle by the atomizing spray device of the present invention. In FIG. 9, reference numeral 41 denotes an electrolytic solution that is a viscous liquid, and the electrolytic solution that has become droplets 46 from the nozzle 44 lands on the mixture in the EDLC container 50. The electrolytic solution is a droplet having a particle size of several tens to 100 μm at intervals, and absorption into a mixture, which has not been easy in the past, proceeds. Furthermore, if the number of nozzles is increased, the particle size of the droplets is reduced, and the time interval is increased, the absorption into the mixture can be more efficiently proceeded.

11, 42 Nozzle plate 12, 44 Nozzle 13, 43 Vibrator 15 Nozzle outlet side 21, 41 Viscous liquid 14, 52 Pulse generation drive circuit (electric signal generating means)
45 Resistance temperature sensor (temperature detection means)
51 Microcomputer (Determination means)
52 Drive circuit (electrical signal generating means)

Claims (6)

A nozzle plate having a large number of nozzles to which viscous liquid is supplied; a vibrator for vibrating the nozzle plate or the viscous liquid; and an electric signal generating means for intermittently repeating vibration and stop of the vibrator. have a, a in the plurality of atomizing spray device the spray outlet is blocked nozzles liquid pool of the viscous liquid to a spray outlet surface of the nozzle plate adjacent caused by successive atomization spraying of the viscous liquid Te, the electrical before spraying outlet of said plurality of nozzles spraying outlet of the nozzle plate adjacent said viscous liquid puddle occurs in the spray outlet surface of the nozzle plate by the continuous atomization spray is blocked An atomizing and spraying apparatus characterized in that the vibration of the vibrator is stopped by the signal generating means, and the intermittent operation is performed to vibrate the vibrator again after the stop .   Viscosity having atomizing and spraying from the nozzle according to the length of the electric signal, having detecting means for detecting the temperature of the viscous liquid and determining means for determining the length of the electric signal according to the detected temperature The atomization spray apparatus of Claim 1 which controls the liquid quantity.   The atomizing spray apparatus according to claim 1 or 2, wherein the viscous liquid has a high viscosity of 10 to 40 mPa · s at 20 ° C.   The atomization spray apparatus according to any one of claims 1 to 3, wherein the viscosity of the viscous liquid is 10 mPa · s or more and the vibration time is 20 ms or less.   The atomization spray apparatus according to any one of claims 1 to 3, wherein the viscosity of the viscous liquid is 30 mPa · s or more and the vibration time is 10 ms or less. The atomizing spray device according to claim 1, wherein the nozzle plate has a distance between adjacent nozzles of 150 μm or more.