WO2004087342A1

WO2004087342A1 - Cavitation-generating device

Info

Publication number: WO2004087342A1
Application number: PCT/JP2004/004058
Authority: WO
Inventors: Masahisa Fujimoto
Original assignee: Masahisa Fujimoto
Priority date: 2003-03-28
Filing date: 2004-03-24
Publication date: 2004-10-14

Abstract

A cavitation-generating device has a cavitation block where a cavitation chamber is partitioned. In the cavitation chamber is placed a liquid. Vibration pistons are opposedly arranged in the cavitation block. Each vibration piston slides so as to approach to and depart from the cavitation chamber. The vibration pistons are driven by a link mechanism and a crank mechanism and vibrate at predetermined amplitude. Composite amplitude of the vibration pistons is controlled by a control device. In the cavitation block are provided inertia pistons. The inertia pistons are opposedly arranged so as to face the cavitation chamber and reciprocate so as to approach to and depart from the cavitation chamber. The liquid in the cavitation chamber is circulated. The liquid circulated is deaerated by a liquid separator.

Description

Description Cavitation generator Technical field

The present invention relates to an apparatus and a method for generating cavitation. “Cavitation” is a phenomenon in which shock waves are generated when bubbles generated in a liquid are destroyed. Background art

In devices that handle fluids, cavitation may occur in general. Specifically, the pressure of the fluid handled by the device generally varies locally at all times. When the pressure of the fluid drops below the saturated vapor pressure of the fluid, the fluid evaporates and bubbles are generated. However, when the pressure of the fluid fluctuates greatly, the pressure of the fluid instantaneously exceeds the saturated vapor pressure, and the bubbles are destroyed. At this time, a large shock wave is generated. The mechanical force of this shock wave is generally very large. Therefore, if cavitation occurs in a fluid handling device (eg, pump, turbine), the components of the device may be damaged, and the cavitation is generally regarded as harmful.

On the other hand, the shock wave of the cavitation can be used for cleaning, sterilization, sterilization, etc. of articles. For this reason, a device that actively generates cavitation has been provided. Conventional cavitation generators include those that emit ultrasonic waves into a liquid such as water, those that eject high-pressure water in water, and those that eject high-pressure air in water. These various types of cavitation generators have already been put into practical use. In order for the cavitation shock wave to be used effectively, it is desirable that the generation and destruction of air bubbles occur continuously in a very short time. However, conventional cavitation generators were inefficient in generating and destroying bubbles. As a result, conventional cavitation generators did not exhibit high cleaning or sterilizing effects.

Therefore, an object of the present invention is to provide a cavitation generator that has high efficiency of generation and destruction of air bubbles and can perform powerful cleaning and sterilization. Disclosure of the invention

The basic principle of the present invention will be described with reference to FIG.

The liquid tank 1 is formed in a cylindrical shape, and the upper part thereof is open to the atmosphere. A vibration piston 4 is provided below the liquid tank 1. The vibration piston 4 is connected to the electric motor via a crank mechanism. The crank mechanism includes a crank shaft 8, a crank pin 6, and a crank rod 5. Rotational movement of the crankshaft 8 is converted into vertical movement of the vibration piston 4, which slides up and down the inner wall of the liquid tank 1.

Liquid tank 1 is filled with liquid 2 (typically water). When the crankshaft 8 rotates, the oscillating piston 4 reciprocates up and down, and the liquid 2 present above the oscillating piston 4 reciprocates up and down together with the oscillating piston 4. The lower part of the vibrating piston 4 is filled with a compressible gas (typically, air). Since the vibration piston 4 has the seal (O-ring) 4a, the liquid fluid 2 does not leak to the crank mechanism side.

The force acting on the liquid 2 in the liquid tank 1 is the product of the acceleration of the liquid 2 and the mass of the liquid. The acceleration of the liquid 2 is provided by the oscillating piston 4. The value of the force acting on liquid 2 reduced by the cross-sectional area of liquid tank 1 depends on the inertia of liquid 2. Pressure. The value obtained by adding the atmospheric pressure acting on the liquid level 3 of the liquid tank 1 to this pressure is the absolute pressure of the liquid 2.

The reciprocating motion of the oscillating piston 4 and the liquid 2 is expressed by the following equations (Equations 1 to 3). Here, the rotational angular velocity of the crankshaft 8 is _ω (rad), and the amount of eccentricity of the crankpin is a (m). However, these equations show the state until bubbles are generated. This is because, when bubbles are generated, the motion state of the liquid 2 above the bubbles changes. In other words, the acceleration of the liquid 2 becomes smaller than the vibration piston 4 due to the generation of bubbles.

Vertical movement of vibration piston (m): z = a sincot (Equation 1) Vertical velocity of vibration piston (m / s): v = acocoscot (Equation 2) Vertical acceleration of vibration piston (M2 / s ² ): a = _aco ² sincot (Equation 3) The mass of the liquid 2 from the liquid level 3 to the position of the depth H (m) and the acceleration α of the liquid 2 expressed by the above (Equation 3) The product is the force applied to the liquid 2 by the oscillating biston 4. The value obtained by reducing this force by the cross-sectional area of the liquid tank 1 indicates the pressure of the liquid 2. Therefore, the pressure PH (Pa) of the liquid 2 generated at the position of the depth H (m) from the liquid level 3 due to the reciprocation of the liquid 2 is

PH = P a— SHT / aco ² sino> t / S (Pa) (Equation 4)

= P a— H γ a o 'sinco t (Pa)

Where Pa: Atmospheric pressure (Pa)

S: Cross-sectional area of liquid tank 1 (m ² )

7: Specific gravity of liquid (kg / m ³ )

As shown in (Equation 4), the cross-sectional area S of the liquid tank 1 has no relation to the behavior of the pressure PH.

If the minimum pressure PH (Pa) shown by (Equation 4) is lower than the saturated vapor pressure (Pv) of water, part of the liquid 2 will boil and evaporate, and bubbles will be generated. Table 1 shows the generation of air bubbles when water is used as liquid 2. ing. In this table, the atmospheric pressure is 101325 Pa, and the specific gravity γ of water is 1000 kg / m ³ . In addition, the frequency == 50 Hz.

The saturated vapor pressure (Pv) of water is 1710 Pa at a temperature of 15 ° C and 234 OPa at a temperature of 20 ° C. Therefore, the critical water depth HL for bubble generation is about 0.5 m. Pressure PH drops below the saturated vapor pressure (Pv) of water The time is as short as a few milliseconds. The generated bubbles occur throughout the region where the pressure PH has dropped below the saturated vapor pressure (Pv). Also, the heat of vaporization is necessary for the generation of bubbles. Therefore, even if bubbles receive heat from the surrounding water, the generation of bubbles is an instantaneous phenomenon. For this reason, the bubbles cannot grow large and the diameter of the bubbles is less than several dragons.

(Equation 4) Force, et al., H = (P a-PV) / a co ² s in co t

HL = (P a - P v ) / (a ω 2) (m) ( Equation 5)

H L: Limit water depth for bubble generation (m)

Pv: Saturated steam pressure of water (Pa)

As shown in (Equation 4), the deeper the depth H from the water surface, the lower the minimum pressure. Therefore, bubbles are generated first on the piston face of the vibrating piston 4 and then on the upper part thereof. When the position of the oscillating piston 1 is deeper than the critical water depth H L, no bubbles are generated up to the critical water depth H L. Bubbles are generated most in the vicinity of the oscillating piston 4, and the amount of bubbles decreases as the position becomes higher than the oscillating piston 4. This is because, when bubbles are generated, the volume of the bubble generating section increases, and the acceleration α of the water above the bubble generating section decreases.

The generated bubbles are destroyed when the pressure of the liquid 2 recovers immediately. That is, the bubbles collapse and become the original liquid 2. At that time, a large shock wave is generated (cavitation phenomenon).

The present invention has the following features as compared with the conventional one.

(1) Large bubble generation volume (ratio of bubble volume to volume of liquid 2 present in bubble generation section) and large bubble generation range. As shown in the figure, the volume of generated bubbles can be adjusted to several% to several tens% of the displacement of the vibrating piston 4. The bubble generation range is from the piston face of the vibrating piston 4. The maximum water depth is up to HL.

In the conventional cavitation generator using ultrasonic waves, cavitation is generated only on the side where the ultrasonic transducer is installed, and on the other side, the generation of cavitation is drastically reduced. In a conventional cavitation generator using a jet of high-pressure water, cavitation is generated only on the jet side of high-pressure water, and on the opposite side, the generation of cavitation is drastically reduced. On the other hand, in the case of the present invention, the generation and destruction of air bubbles occur in a preset space, and even when the article to be washed has a complicated structure, cavitation may occur on the entire surface. Therefore, the conventional cavitation generator is mainly used for cleaning instruments and equipment, whereas the cavitation generator according to the present invention is also used for sterilization (sterilization) of medical instruments and kitchen appliances. obtain.

(2) High efficiency of bubble generation and destruction. The reciprocating motion of the oscillating piston 4 is almost consumed only for the generation and destruction of bubbles. Therefore, highly efficient operation can be achieved epoch-making compared to the conventional cavitation generator.

However, the cavitation generator shown in Fig. 1 has the following points to be improved.

(1) Configuration of vibration biston

In the vibration piston 4 of the cavitation generator shown in FIG. 1, the rotational imbalance of the crank shaft 8 is large, and large vibration and noise are generated. As a countermeasure, a counterweight is provided on the crankshaft 8. However, since the mass of the liquid 2 has a great influence, the rotational imbalance of the crankshaft 8 is not effectively reduced.

Also, in the cavitation generator shown in FIG. 1, the stroke is smaller than the diameter of the oscillating piston 4. This means that This makes it difficult to actually design and manufacture the generator. It is possible in the design calculation that the piston diameter of the oscillating piston is set small and the stroke is increased. However, the sliding speed of the oscillating piston 4 increases, and the generation rate of bubbles near the oscillating piston 4 increases. Therefore, the operation efficiency of the cavitation generator is greatly reduced.

As a countermeasure, an opposing piston (a pair of oscillating pistons 14) shown in FIG. 2 is provided instead of the oscillating piston 4. As shown in the figure, the crankshaft rotates about the crankshaft center 8a, but the crankpin rotates on the crankpin track 6a about the crankshaft. The diameter of the crank pin orbit 6a is the stroke amount (twice the eccentric amount) of the vibrating biston 14. The positions of the crankpins of the vibration piston 14 are symmetrically arranged on the crankpin track 6a about the crankshaft center 8a.

Furthermore, as shown in Figure 2, the crank rod has been eliminated. As a result, the oscillating biston bearing is directly reciprocated by the crank pin.

The oscillating biston 14 reciprocates and swings. The amount of eccentricity of the crank pin is sufficiently small with respect to the piston diameter of the oscillating piston 14 and is substantially the same as the case where the crank rod is provided (the swing motion is ignored). Of course, a crank rod may be provided.

Figure 2 shows the left and right angles of rotation of the crankshaft at 0 ° (thin line; bottom dead center), 60 ° (dashed line), 120 ° (dash-dot line), and 180 ° (solid line; top dead center). The state of the oscillating biston 14 is illustrated. As described above, the force applied to the left and right vibration pistons 14 and the movement of the left and right vibration pistons 14 are always symmetric about the crankshaft center 8a of the crankshaft. In other words, the provision of a pair of opposing vibration The rotational impedance of ton 14 is theoretically zero. Therefore, the vibration and noise of the cavitation generator are greatly reduced.

(2) Operation method

The vibration biston 4 shown in FIG. 1 is driven by the electric motor as described above. However, the response speed is slow due to the inertia of the rotating part, and it takes a long time to start or stop the vibration piston 4. In addition, air bubbles are generated and destroyed while the cavitation generator is on standby (when replacing the equipment to be cleaned, etc.), which makes handling the cavitation generator inconvenient.

As a countermeasure, as shown in FIG. 2, a plurality of vibrating bistons 14 are provided, and each vibrating piston 14 is provided with a rotation speed control device such as an impeller. As a result, the rotation speed and phase difference of each vibration piston '14 are controlled, and the magnitude of the combined amplitude and the generation or interruption of bubbles are controlled with a quick response.

For example, as shown in FIG. 2, if the phase difference between the vibration pistons 14 is zero degrees, the composite amplitude becomes maximum. If the phase difference is 180 degrees, the resultant amplitude is zero. Therefore, when the cavitation generator is started up and the stand-by is stopped, the phase difference between the inverters is set to 180 degrees (reverse phase shift), and the generation and destruction of air bubbles is extremely small (almost zero). . As a result, the start and stop of the cavitation generator are quickly executed, and the motor does not need to be stopped when the cavitation generator is on standby (replacement of equipment to be cleaned, etc.), thereby improving work efficiency.

In addition, when each of the vibration pistons 14 is operated so as to have a different frequency, the magnitude of bubble generation changes periodically. That is, “beat vibration operation” with the frequency difference as the cycle occurs.

(3) Depth of bubble generation or destruction

In the cavitation generator shown in Fig. 1, the critical depth HL of bubble generation is large (about 0.5 m), and the handling of the device is not easy. Bubbles Preferably, birth and destruction occur in more shallow locations.

As a countermeasure against this, as shown in Fig. 3, an inertia piston 44 is provided at the top of the place where bubbles are generated and destroyed. The inertia piston 44 is arranged above the bubble generation and destruction part 60. The inertia piston 44 is made of metal, and is slidable along the inner wall surface of the liquid tank 1. Since the inertia piston 44 is made of metal, the inertia is increased in a compact manner. However, the material of the inertial piston 44 is not limited to metal. Due to the inertia of the inertia piston 44, the depth at which bubbles are generated in the liquid 2 is reduced.

The pressure below the inertial piston 44 is given by the following equation.

PH = P a-(K + Waco ² sinco t) / S (Pa) (Equation 6) where

W: Mass of inertial piston 44 (Kg)

K: Force of lifting device 4 6 (N)

Other symbols are the same as in (Equation 4).

If the force of the lifting device 46 is zero, (Equation 6) is obtained by replacing S * H * o / in (Equation 4) with W. If the inertial bistone 44 is made of stainless steel or steel, the critical water depth HL at which bubbles are generated due to the difference between the specific gravity of the inertial biston 44 and the specific gravity of water is determined as follows. This is about one-eighth that of the case where it is not provided.

Further, by adjusting the force of the suspension device 46, the influence of the atmospheric pressure is avoided. That is, as the force of the suspension device 46 increases, the average pressure of the bubble generation and destruction section 60 decreases. Therefore, unlike the cavitation generator shown in FIG. 1, it is not necessary to increase the maximum pressure to about 2 atm in order to generate air bubbles. As a result, the operating range of the cavity generation device is expanded, and the driving power is reduced. In the cavitation generator shown in FIG. 3, the inertia piston 44 is suspended by a leaf spring, but the inertia piston 44 can slide along the liquid tank 1 and satisfies (Equation 6). As long as the suspension device 46 is used, a coil spring, a counter panel, a pneumatic panel, or the like may be used instead of the plate panel.

(4) Bubble generation at the vibration piston

In the cavitation generator shown in FIG. 1, the generation and destruction of bubbles occur in a region deeper than the limit water depth HL determined by the frequency and stroke of the vibrating biston 4. However, theoretically, bubbles are likely to be generated on the piston surface of vibrating piston 4 (especially near vibrating piston 4). In particular, as shown in FIG. 2, when the vibrating pistons 14 are arranged to face each other, the generation rate of bubbles near the vibrating pistons 14 increases, and the efficiency of the cavitation generator may be reduced. is there. Therefore, the present inventor tried to limit the bubble generation and destruction part 60 by adjusting the inner diameter of the liquid tank 1. However, its realization is difficult.

As a countermeasure, the cavitation generator shown in Fig. 3 uses a pressurized piston 5 that can slide along the inner wall surface of the liquid tank 1 so that air bubbles are generated and destroyed only in a specific section of the liquid tank 1. 4 or pressurized membrane (not shown) is provided. The pressure piston 54 is pressed against the liquid 2 by a spring mechanism 56 and a pressure pump 58. As a result, the pressure below the pressurized piston 54 does not always fall below the saturated vapor pressure of the liquid 2 during operation of the cavitation generator. As a result, the generation and destruction of air bubbles do not occur at the lower part of the pressurized piston 54 (or hardly occur). In the cavitation generator shown in the figure, the liquid 2 previously stored in the tank 61 is used to pump the liquid Supplied below pressurized biston by 5 8 Is done. However, the liquid 2 may be supplied from another system. Further, the pressure of the supplied liquid 2 is adjusted by a throttle valve 59. In addition, a pressure film may be used instead of the pressure piston 54. This pressurized film transmits the vibration of the vibration piston chamber of the liquid tank 1 to the bubble generation and destruction section 60. The pressure film 55 can be reduced in weight as compared with the pressure piston 54.

(5) Gas contained in liquid

Normally, the liquid 2 contains gases such as nitrogen, oxygen, and carbon dioxide in the atmosphere. These gases tend to be nuclei of bubble generation when bubbles are generated. Therefore, the presence of these gases facilitates the generation of bubbles. However, the following characteristics are shown with respect to the collapse of bubbles, which is the original purpose of the cavitation generator.

The gas in the vapor is much less likely to be contained (dissolved) in the original liquid than the vapor becomes the original liquid (water is called condensate). That is, the destruction of bubbles is delayed. Alternatively, it is the nucleus of bubble generation at the stage where bubbles are not completely destroyed and other bubbles are generated. As a result, the shock wave strength at the time of bubble collapse is greatly reduced.

As a countermeasure, in the cavitation generator shown in FIG. 3, when bubbles are generated or destroyed, the degassed liquid 2 is supplied or circulated to the liquid tank 1. As a result, a reduction in the effect of the shock wave caused by the gas contained in the liquid 2 is avoided. In order to deaerate the liquid 2, a deaeration tank 61 is arranged, and a gas contained in the liquid 2 is removed by a vacuum pump 63. Specifically, as shown in FIG. 3, the liquid 2 (degassed liquid) in the degassing tank 61 is supplied to the bubble generation and destruction section 60 of the liquid tank 1 by the circulation pump 62 to the nozzles 64. Is supplied via The liquid 2 is circulated to the deaeration tank 61 via a labyrinth 65 provided at the center of the inertial piston 44. Prolapse A vacuum pump 63 is connected to the gas tank 61. The liquid 2 sent from the bubble generation and destruction section 60 is effectively degassed.

The degassed liquid 2 is supplied from a nozzle 64 provided in the liquid tank 1 into the bubble generation and destruction section 60. As a result, the liquid 2 forms a swirling flow in the liquid tank 1, and bubbles are collected at the center of the swirling flow. As a result, the liquid 2 is effectively degassed. Further, as shown in the figure, the throttle valve 69 is provided, so that the average pressure of the bubble generation and destruction section 60 can be easily adjusted. Therefore, the average pressure of the bubble generation and destruction section 60 can be set to, for example, the atmospheric pressure or less, whereby power for driving the vibration piston 4 is reduced. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a diagram schematically showing the basic principle of the present invention.

FIG. 2 is a diagram schematically illustrating an aspect in which the vibration bistones of the present invention are arranged to face each other.

FIG. 3 is a diagram schematically showing the structure of the cavitation generator according to the present invention.

FIG. 4 is a cross-sectional view of the cavitation generator according to the first embodiment of the present invention.

FIG. 5 is a sectional view taken along line VV in FIG.

FIG. 6 is a diagram schematically showing a configuration of a cavitation generator according to a second embodiment of the present invention.

FIG. 7 is a diagram illustrating a flow of water to be sterilized in the cavitation generator according to the second embodiment of the present invention.

FIG. 8 is a diagram schematically showing a configuration of a cavitation generator according to a third embodiment of the present invention. FIG. 9 is a cross-sectional view of a cavitation block according to a modification of the third embodiment of the present invention.

FIG. 10 is a front view of a crank mechanism according to a modification of the third embodiment of the present invention.

FIG. 11 is a view showing a structure of a driving mechanism for a vibration piston according to a modification of the third embodiment of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described in detail based on preferred embodiments with reference to the drawings as appropriate.

(1) First embodiment

As shown in FIG. 4 and FIG. 5, this cavitation generator has a liquid tank 1, and the liquid tank 1 is formed in a cylindrical shape. The liquid tank 1 can withstand a pressure of several to tens of atmospheres. However, the liquid tank 1 is not limited to a cylindrical shape, and may have another shape as long as it can withstand the above pressure.

The vibration generator 10 is housed in the vibration generator cylinder 11. The vibration generating section cylinder 11 penetrates the liquid tank 1 so as to be orthogonal to the central axis of the liquid tank 1. A seal (O-ring) 11a is provided at the boundary between the vibration generating cylinder 11 and the liquid tank 1.

Motors 19 are installed at both ends of the vibration generating cylinder 11. The motor shaft 18 of the motor 19 rotates about the center axis of the vibration generating cylinder 11. A bearing for rotatably supporting the motor shaft 18 is disposed in the center of the vibration generating portion cylinder 11. This bearing is supported on the inner wall of the vibration generating cylinder 11.

A circular window is provided on the side wall of the vibration generating cylinder 11. This window Cylinder 12 is fitted into the cylinder. The cylinder 12 supports the opposing vibration piston 14. Two sets of opposing vibration pistons 14 are provided. Since the vibration generating section cylinder 11 penetrates the liquid tank 1, the tip of the cylinder 12 is machined into the side wall shape of the cylinder 11.

Each motor shaft 18 passes through two sets of eccentric disks 16 and three flywheels 17. The motor shaft 18 and the eccentric disk 16 and the motor shaft 18 and the flywheel 17 are connected by a spline structure, and rotational torque is transmitted. The bearing 15 is fitted on the outer peripheral surface of the eccentric disk 16, and the vibration bistone 14 is further fitted on the outer peripheral surface of the bearing 15. As the bearing 15, a ball bearing is adopted, but a roller bearing or a slide bearing may be adopted instead.

The amount of eccentricity of the two sets of eccentric disks 16 with respect to the central axis (that is, the motor shaft 18) is half of the amount of stroke of the vibrating piston 14, and the eccentric direction is reversed (the phase is shifted by 180 degrees). Is). Therefore, the opposing oscillating pistons 14 (see FIG. 5) reciprocate in opposition by the rotation of the motor shaft 18.

One (inner) eccentric disk 16 acts on one oscillating piston 14, and the other (outer) eccentric disk 16 acts on the other oscillating piston 14. The reason for this configuration is that the rotational motion of the motor shaft 18 is transmitted to the reciprocating motion of each vibration piston 14 with good balance. The torque required for the oscillating piston 14 to reciprocate is several to several tens times the average rotational torque of the motor shaft 18. This makes it difficult to rotate the motor shaft 18 smoothly. However, in the present embodiment, a plurality of (three) flywheels 17 are provided, and the eccentric disk 16 and the flywheel 17 are connected by a plurality of pins 16a. The smooth rotation of the motor shaft 18, that is, the smooth reciprocation of the vibrating Is achieved.

In FIG. 4, in the upper half of the vibration generator 10, the vibration piston 14 is located at the top dead center, and in the lower half, the vibration piston 14 is located at the bottom dead center. As shown in FIG. 5, two sets of opposing oscillating pistons 14 are provided. In the figure, the upper half is an opposing oscillating piston 14 on one side, and each oscillating piston 14 is It is located at the top dead center. Also, in the same figure, the lower half is the opposing vibration piston 14 on the other side, and each vibration piston 14 is at the position of the bottom dead center. That is, the figure shows a state where the phase difference of the vibration piston 14 is 180 degrees.

Although not shown in FIGS. 4 and 5, each of the electric motors 19 may include a rotation speed control device such as an inverter. In this case, the number of rotations of each motor 19 and the phase difference between the two are controlled, and the magnitude of the combined amplitude, and the generation and interruption of bubbles are controlled with a quick response.

As shown in FIG. 4, a cylindrical inertial biston 44 is disposed above the liquid tank 1. This inertial piston 4 4 is slidable up and down in the figure. The inertia button 44 is provided with a seal mechanism 44a. As the sealing mechanism 44a, for example, an O-ring is employed. This prevents the occurrence of cavitation between the liquid tank 1 and the inertial piston 4 4. Although not shown in FIG. 4, the inertia piston 44 may be suspended on the side wall of the liquid tank 1 by the suspension device 46 shown in FIG. A pressurized biston 54 is arranged at the lower part of the box. A panel mechanism 56 is provided between the pressurized biston 54 and the side wall of the liquid tank 1. The pressurizing piston 54 is pulled downward by the panel mechanism 56. This creates a difference between the pressure at the top of the pressure piston 54 and the pressure at the bottom. Although not shown in FIGS. 4 and 5, as shown in FIG. 3, the liquid 2 pressurized by the pressurizing pump 58 is supplied to the lower part of the pressurizing piston 54. Has become.

Further, the pressure biston 54 is provided with a seal mechanism 54a. This seal mechanism 54a employs an O-ring. This prevents cavitation between the liquid tank 1 and the pressurized piston 54.

When the generated bubbles are destroyed, a shock wave is transmitted to the surface of the vibrating biston 44. This shock wave is not as large as the shock wave generated in the bubble generation and destruction part 60, but a considerably large shock is applied to the vibration piston 14. For this reason, it is necessary to increase the strength of the bearing 15, the eccentric disk 16 and the pin 16 a. Further, in order to reduce the impact applied to the vibration piston 14, the vibration film 14 may be provided with a buffer film 20. The buffer film 20 may be made of an elastic material, such as a rubber film or a plastic film.

(2) Second embodiment

A second embodiment of the present invention will be described based on FIG. 6 and FIG.

The cavitation generator according to the present embodiment is used as a liquid sterilizer (sterilizer). For example, drinking water, bath water, pool water, etc. are circulated through this device to sterilize the water.

The configuration of the cavitation generator shown in Fig. 6 is different from the cavitation generator shown in Fig. 3 in that a storage tank (bath tub, pool, etc.) is arranged in place of the deaeration tank 61, and other configurations. Is the same as the cavitation generator shown in FIG. As shown in FIG. 7, in the present embodiment, the water to be sterilized is supplied from the nozzle 64 to the bubble generation and destruction section 60. The water to be sterilized is sterilized as follows.

Water from the drinking water source, bathtub or pool (water to be sterilized) is discharged from one or more nozzles 64 to the cavitation generating device. Sent to section 60. The water to be sterilized flows into the outer periphery of the bubble generating and destroying section 60 while forming a spiral flow, and is discharged from the center of the bubble generating and destroying section 60. At this time, the bacteria contained in the water to be killed are killed in a short time by the shock wave generated in the entire area of the bubble generating and destroying part 60.

(3) Third embodiment

A third embodiment of the present invention will be described with reference to FIG.

The cavitation generator according to the present embodiment has the following characteristic configuration.

① The vibration pistons have a pair structure, and the pressure faces (surfaces facing the inside of the cavitation chamber) of each vibration piston face each other. Each vibration piston is driven by a link mechanism and a crank mechanism.

(2) The inertial pistons have a pair configuration, and each inertial piston faces each other. Each inertial piston faces the interior of the cavitation chamber in the same manner as the above-mentioned vibration piston.

③ The cavitation chamber has a symmetric structure. As a result, the liquid in the cavitation chamber moves due to the reciprocating motion of the vibration biston and the inertia biston, or due to the generation and destruction of bubbles and the pressure fluctuation in the cavitation chamber. Does not occur.

高速 A high-speed circulation deaeration system consisting of a check valve and a gas-liquid separator is provided. This constrained circulation degassing system utilizes pressure fluctuations in the cavitation chamber. As a result, gas (non-condensed gas) in the liquid is quickly discharged from the cavitation chamber. As a result, the symmetry of the cavitation chamber is maintained and quick degassing is possible due to the imbalance caused by the remaining non-condensable gas.

In the cavitation generator having the above configuration, vibration and noise are greatly reduced. As shown in FIG. 8, the cavitation block 101 has a rectangular parallelepiped outer shape, and a cavitation chamber 102 (bubble generation and destruction chamber) is provided inside. The cavity block 101 is provided with holes each having the X-axis and the z-direction axis passing through the center thereof as central axes. A vibration piston 114 is fitted into a hole provided along the X-direction axis, and the vibration piston 114 slides in the X direction. An inertia button 144 is fitted into a hole provided along the z-axis, and the inertia button 144 slides in the z-direction. The cavitation block 101 may be made of metal or plastic as long as it can withstand the shock wave at the time of bubble collapse. The outer shape of the cavitation block 101 is not necessarily a rectangular parallelepiped, but may be a sphere, a cylinder, or an ellipse.

In this cavitation generator, the X-axis and the z-axis are set so as to pass through the center of the cavitation chamber 102. This is for ease of explanation. Thus, the X-axis and the z-axis do not necessarily need to pass through the center point of the cavitation chamber 102. Further, since the vibration and noise due to the liquid in the cavitation chamber 102 are smaller than the vibration biston 114 or the inertia bistone 144, the above-mentioned configuration ③ may not be adopted.

The pair of vibrating biscuits 111 are coupled to the leper 107. One end of each of the repellers 107 is connected by a repeller 110, and a fulcrum 108 is formed therebetween. Each vibrating stone 114 slides with respect to the hole in the X direction axis of the cavity chamber 102. The other end of each repeller 107 is connected to a motor. The rotating shaft of the electric motor is connected to each lever 107 via a crank mechanism. The rotating motion of the rotating shaft of the electric motor is coupled to the crank rod 105 converted into reciprocating motion by the crank mechanism via the bearing 109. This bearing 109 is connected to the other end of each lever 7 Constitute the side fulcrum. When the electric motor 1 19 rotates, the lever 1 07 makes a pendulum movement about the fulcrum 1 0 8. As a result, the vibrating piston 114 coupled to the leper 107 reciprocates in the X-axis.

At this time, since the position of the crank pin 106 is at a symmetrical position (same eccentricity) about the motor shaft 118, the pair of vibrating pistons 114 is located at the center of the cavitation chamber 102. Reciprocate symmetrically around. A sealing device such as an O-ring is provided on the outer peripheral surface of the vibrating piston 114 to prevent the liquid in the cavitation chamber 102 from leaking to the outside.

The pair of raw pistons 144 slide with respect to a hole in the z-axis of the cavitation block 101. The reciprocating motion of the oscillating piston 144 is transmitted to the inertia piston 144 via the liquid in the cavitation chamber 102.

The panel device 144 supports the inertial biston 144. Thus, the inertial piston does not come off the cavitation block 101 by moving along the z-direction axis. However, the panel force of the spring device 144 need only be such that the displacement of the inertial piston 144 due to gravity in the sliding direction (z direction) is corrected. However, when the average pressure in the cavitation chamber 102 is changed from the atmospheric pressure, it is necessary to adjust the spring reaction force according to the pressure. In addition, a sealing device such as an O-ring is provided on the outer peripheral surface of the inertial piston 144 so that the liquid snapper in the cavitation chamber 102 does not leak outside. The gas-liquid separator 166 is connected to the cavitation chamber 102. The upper part of the cavitation chamber 102 and the gas-liquid separator 166 are connected via a check valve 166, and the drainage of the gas-liquid separator 166 is connected to the check valve 1 It is sent to the lower part of the chamber 102 via 68. In addition, A nozzle 169 is provided below the chamber 102, whereby the liquid in the cavitation chamber 102 circulates. The exhaust from the gas-liquid separator 166 may be released to the atmosphere or may be connected to a degassing system.

The pressure of the cavitation chamber 102 fluctuates greatly from the saturated pressure of the liquid to a pressure of about twice the atmospheric pressure during operation of the cavitation generator, and the fluctuation is repeated. Since the gas-liquid separator 166 is open to the atmosphere or connected to another system, the pressure fluctuation of the gas-liquid separator 166 is small. The inventor of the present application paid attention to this point and constructed the following circulation system. That is, when the pressure in the cavitation chamber 102 is higher than the pressure of the steam separator 166, the liquid in the cavitation chamber 102 flows from the upper pipe of the cavitation chamber 102 to the check valve 1. It flows into the steam separator 16 through 6 7. At this time, in the pipe connected to the lower part of the cavitation chamber 102, the flow of the liquid is shut off by the check valve 168. When the pressure in the cavitation chamber 102 is lower than the pressure of the gas-water separator 166, the drainage of the gas-liquid separator 166 passes through the check valve 168 to the cavitation chamber. Flow into 102. At this time, in the pipe connected to the upper part of the cavitation chamber 102, the flow of the liquid is blocked by the check valve 167.

Further, the nozzle 169 is provided below the cavitation chamber 102, so that the inflowing liquid is jetted in the circumferential direction of the cavitation chamber 102. Therefore, the liquid in the cavitation chamber 102 swirls. As a result, a centrifugal force acts on the liquid in the cavitation chamber 102, and bubbles of the non-condensed gas having a small specific gravity are collected in the center of the swirling flow, that is, in the center of the liquid in the cavitation chamber 102. .

Therefore, the condensed gas is supplied to the upper piping of the cavitation chamber 102. Is effectively discharged from As a result, the non-condensable gas in the cavitation chamber 102 flows into the gas-liquid separator 166 together with the liquid in the cavitation chamber 102, and is separated from the liquid by the gas-liquid separator 166 and discharged to the atmosphere. Is done. The liquid from which the non-condensable gas has been separated and removed is returned to the cavitation chamber 102 again.

In the present embodiment, the pipe connected to the upper part of the cavitation chamber 102 is attached to the inertial piston 144, but this pipe is connected to the top of the center of the cavitation chamber 102. It should just be. Therefore, when the vibrating biscuit 114 is located at the top of the cavitation chamber 102, the above piping is attached to the vibrating piston 114, and If the top of 102 is the cavitation block 101, then the tubing is attached to this cavitation block.

Further, in the present embodiment, the piping connected to the lower portion of the cavitation chamber 102 is attached to the lower portion of the cavitation block 101, but is not limited to this. In short, the pipe may be provided so that the liquid ejected from the nozzle 169 generates a swirling flow in the liquid in the cavitation chamber 102.

(4) Modification of the third embodiment

A modification of the third embodiment of the present invention will be described with reference to FIGS. 9 to 11.

As shown in FIG. 9, in this modification, the cavity block 101 is formed in an octagonal cylindrical shape in cross section. The cavity block 101 is provided with a cylindrical cavity chamber 102 (bubble generation and destruction chamber) inside. The X-axis, Y-axis, X passing through the center of the cavitation chamber 102 Holes are provided with the y-axis and the y-axis as the central axes, respectively. Vibration bistons 114 are fitted in the holes in the X-axis and the y-axis, and the vibration bistons 114 slide with respect to the cavitation block 101. In addition, inertia pistons 144 are fitted in the holes in the X-y axis and the y-X axis.

The cavitation chamber 102 is formed in a cylindrical shape extending in the z direction of the cavitation block 101. Although not shown, a ceiling plate and a bottom plate sealed with an O-ring or the like are provided at the top and bottom of the cavitation chamber 102. When the ceiling plate and the bottom plate are made of transparent plastic or the like, the state of occurrence of cavitation can be easily observed from the outside. The cavity block 101 may be made of metal or plastic as long as it can withstand the shock wave at the time of bubble collapse. The external shape of the cavity block 101 is not necessarily an octagonal prism, but may be a sphere, a cylinder, or an ellipsoid.

Further, as shown in FIG. 11, in this modified example, the drive mechanism of the vibrating biston 114 is disposed immediately below the cavitation block 101. This drive mechanism includes four levers 107, which are raised in the z direction, and are connected to the connection lever 110 at the upper part of the cavitation block 101. This connecting part forms a fulcrum 108.

As FIG. 9 shows, the two pairs of oscillating pistons 114 are connected to lever 107. This connecting part forms a fulcrum 108. The oscillating piston 111 slides with a hole in the X-axis and a hole in the y-axis provided in the cavitation block 101.

As shown in FIG. 10 and FIG. 11, the other end of the lever 107 is connected to the crank port 105. This connecting part forms a fulcrum 109. K The rank rod 105 constitutes a crank mechanism that converts the rotational motion of the electric motor 119 into a reciprocating motion.

The rotation of the electric motor 119 causes the reper 107 to perform a pendulum movement about the fulcrum A108. As a result, the vibration piston 114 connected to the repeller 107 reciprocates in the X-axis and the y-axis. At this time, the crankpin 106 for the X-axis and the crankpin 106 for the y-axis are symmetrically positioned with the same amount of eccentricity with respect to the center of the motor shaft 118. The pair of vibration bistons 114 reciprocate symmetrically around the center of the cavitation chamber 102 along the X-axis and the y-axis, respectively. The crank mechanism will be described in more detail.

As FIG. 11 shows, the motor shaft 1 18 which is the output shaft of the motor 1 19 is a flywheel 1 17 of a crank mechanism for the X direction axis, an eccentric disk 1 16, a flywheel 1 1 7 And the clutch 120. These are fitted by a spline structure or the like, and rotational torque is transmitted. A bearing 115 is fitted on the outer peripheral surface of the eccentric disk 1 16, and a crank rod 105 is further fitted on the outer peripheral surface. The eccentric disk 1 16 instead of the crank pin is adopted because the eccentric amount of the eccentric disk 1 16 is set small, so that the eccentric disk 1 16 and the motor shaft 1 18 This is to avoid interference.

The output shaft 1 2 1 of the clutch 1 2 0 passes through the flywheel 1 1 7, the eccentric disk 1 1 6, the flywheel 1 1 7 and the clutch 1 2 0 of the crank mechanism for the y-axis. . These are fitted with each other to transmit the rotational torque. In this figure, this portion is shown as viewed from the y direction for simplification of the description. When the cavitation generator is operated to generate and destroy bubbles, the eccentric disk 116 for the y-axis must be eccentric relative to the eccentric disk 106 for the x-axis. Is 90 degrees Is set to be

The clutch 120 is not for the main purpose of engaging or disengaging the motor shaft 118 and the output shaft 121 of the clutch 120, but for the X-axis during the operation of the cavitation generator. It is intended to switch the phase difference between the crank mechanism for the y-axis and the crank mechanism for the y-axis. In the first embodiment, the phase difference between the two sets of crank mechanisms is controlled by the two electric motors. In this cavitation generator, the clutch 120 realizes the function. Detailed description of the structure of the clutch is omitted. The clutch 120 is remotely controlled by an electromagnet or compressed air, but may be manually operated. Further, the clutch 120 may be built in the flywheel 117.

The two pairs of inertia pistons 144 (see FIG. 9) slide with respect to the holes of the cavitation block 101 in the X and Y axes. Similar to the first embodiment, the motion of the inertia piston 144 is performed by transmitting the reciprocating motion of the vibrating biston 114 via the liquid in the cavitation chamber 101. Is

As in the first embodiment, the main purpose of the panel device 146 is to support the inertia biston 144 so as not to come off the cavitation block 101. Therefore, it is sufficient that the panel device 144 has sufficient panel force in the sliding direction of the inertial piston 144 to such an extent that the displacement due to gravity is corrected. However, when the average pressure in the cavitation chamber 101 is changed, the spring force needs to be adjusted according to the pressure. In addition, also in this cavitation generating device, similarly to the first embodiment, the outer peripheral surface of the inertia piston 144 is sealed by a sealing device such as an O-ring, so that the liquid in the cavitation chamber 101 is discharged to the outside. So that it does not leak. Sterilization (sterilization) by a cavitation generator is more effective than other sterilization methods for the following reasons.

Since bacteria contained in the water to be sterilized are living organisms, they have a high gas content and are likely to become nuclei when bubbles are generated. That is, bacteria receive the largest shock wave when the bubble collapses.

Due to the generation of bubbles in the entire region of the bubble generation and destruction section 60 and the swirling flow due to the water supply, the residence time of water in the bubble generation and destruction section 60 is made uniform. Therefore, a part of the water to be sterilized is not discharged without being sterilized, so that reliable sterilization is achieved.

Energy consumption is extremely low and sterilization efficiency is high compared to the conventional high-temperature sterilization method.

There is no need to consider phytotoxicity as compared to the chlorination and chemical sterilization injection methods. Industrial applicability

INDUSTRIAL APPLICABILITY The present invention is applied to a device for generating cavitation, and has the following unique effects. Therefore, the cavitation generator according to the present invention can be used for sterilization (sterilization) of medical equipment and kitchen appliances.

(1) Highly efficient cavitation generation is realized.

(2) There is no direction for the occurrence of cavitation.

(3) Vibration and noise are reduced by arranging the vibration pistons facing each other.

(4) By providing a plurality of pairs of vibrating pistons arranged opposite to each other, the control of the generation and destruction of bubbles can be improved.

(5) By providing the inertial piston and the pressurized piston, the area where bubbles are generated or destroyed is limited. (6) Cavitation with high sterilizing effect is generated by reducing the gas contained in the liquid.

Claims

The scope of the claims

1. Vibrating bistons facing each other facing the cavitation chamber filled with liquid,

A link mechanism and a crank mechanism for moving each vibration biston back and forth with respect to the cavitation chamber;

A cavitation generator comprising a control device for controlling the combined amplitude of each vibration biston.

2. There is provided an inertia button which is arranged so as to face the above-mentioned cavitation chamber, and which is capable of reciprocating in the direction of moving forward and backward with respect to the cavitation chamber.

The cavitation generator according to claim 1, wherein the inertial bistons are arranged symmetrically with respect to the center of the cavitation chamber.

3. a circulation path through which the liquid in the cavitation chamber is circulated in a predetermined direction;

3. The cavitation generator according to claim 1, further comprising: a check valve, a steam separator, and a check valve which are sequentially provided on an upstream side of the circulation path.