JPH1190330A - Ultrasonic radiation apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the intrusion of foreign matter into products even if a failure occurs in mechanical parts by providing the subject apparatus with a diaphragm, an ultrasonic exciting means for exciting this diaphragm and a sound field forming means for changing the directions of sound waves in all directions of the diaphragm and forming a sound field having a linear sound wave focus. SOLUTION: The diaphragm 7 of an ultrasonic radiation apparatus 1 makes deflection vibration in longitudinal and transverse directions based on the longitudinal vibration of a vibrator 19 transmitted through a horn 20. Ultrasonic waves are generated from both the front and rear sides of the diaphragm 7 by this vibration. The sound waves generated toward a vertical direction as shown by arrows a1, b1, from the front and rear sides of the diaphragm 7 in the sound field forming means 30 are reflected and are changed in the direction by parabolic reflection plates 31, 32 as shown by arrows a2, b2. These sound waves head approximately toward the horizontal direction and passes the linear sound wave focus aligned to an x-axis. Then, the vibration energy generated from the rear side of the diaphragm 7, i.e., the side where ultrasonic vibration exciting means exists acts effectively as well.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic wave radiating device suitable as, for example, a bubble eliminating device.

[0002]

2. Description of the Related Art In a beverage maker handling beer, fruit juice, milk, etc., when a beverage is filled in a container and stoppered, a foam generated in a head space of the container is quickly erased. Is used to In particular, this foam is generated when a beverage is put in a container, and from the viewpoint of inconvenience of overflowing from the mouth of the container and hygiene, a process for eliminating the foam is incorporated in the production line. Have been.

FIG. 8 shows a conventional example of such a bubble eliminating device. This apparatus is disclosed in Japanese Patent Application Laid-Open No. 6-191595.

[0004] As shown in FIG. 8, this bubble elimination device is constituted by an oscillator 101, a horn 102 and a diaphragm 103.
3 is excited at high frequency. Specifically, bending vibration is performed as shown by a symbol W in FIG.

[0005] When the diaphragm 103 vibrates, the bubbles B in the container 107 conveyed therebelow by the conveyor 105 become:
It is sequentially erased from above by ultrasonic waves.

Next, a second conventional bubble elimination device will be described with reference to FIG. This bubble elimination device is also disclosed in Japanese Patent Application Laid-Open No. 6-191595.

[0007] As shown in FIG.
Reflector 10 for reflecting sound waves emitted from diaphragm 103
9 is provided. The reflecting plate 109 is formed in a curved shape, and reflects the sound wave emitted from the diaphragm 103 so as to concentrate on one location, that is, toward the bubble B. FIG.
0, the traveling direction of the reflected wave is
This is indicated by 0c.

[0008] By concentrating the sound waves in this manner, the efficiency of use of the vibration energy is increased, and the disappearance of the bubbles B is accelerated.

[0009]

In the bubble elimination device shown in FIGS. 8 and 10, the diaphragm 103 and the screw 112 fastening the diaphragm 103 are damaged due to metal fatigue due to long-term operation, and the container 107 is not moved. There is a risk of getting inside.

Therefore, even when a mechanical part such as a diaphragm is damaged as in the above-described bubble eliminator, no foreign matter is mixed into the product, and stable operation for a long time can be ensured. It is desired to be able to improve the work efficiency.

SUMMARY OF THE INVENTION The present invention has been made in view of these demands, and a foam elimination device for achieving the above object has been proposed.
That is, it is a main object to provide an ultrasonic radiation device.

Further, the present invention provides not only the above effects, but also
It is still another object of the present invention to provide an ultrasonic wave radiating device that can exhibit other effects.

[0013]

In order to achieve the above-mentioned main object, the present invention adopts the following constitution.

An ultrasonic wave radiating apparatus according to the present invention has a vibration plate, ultrasonic excitation means for exciting the vibration plate, and a direction of sound waves in all directions of the vibration plate, and has a linear sound wave focal point. Sound field forming means for forming a sound field.

In the above ultrasonic radiating device, the vibration energy generated from the back side of the diaphragm, that is, from the side where the ultrasonic excitation means is located, effectively acts on the radiation target such as bubbles. Since a sound field having a linear sound wave focal point is formed, it is possible to improve the efficiency of energy utilization for a radiation target.

[0016]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view of an ultrasonic radiation device according to a first embodiment of the present invention, and FIG. 2 is a schematic perspective view of the device and a conveyor.

The ultrasonic wave radiating device according to the first embodiment is used as a bubble eliminating device for eliminating bubbles overflowing in a head space of a container filled with beer or the like.

As shown in FIGS. 1 and 2, the ultrasonic wave radiating device 1 has a long rectangular plate-shaped vibrating plate 7 extending in the direction in which each container 3 is to be conveyed by the conveyor 5. . As the material of the diaphragm 7, a metal, for example, duralumin or the like is selected.

The conveyor 5 transports the container 3 filled with foam to the head space so as to be used for the defoaming operation by the ultrasonic radiating device 1. The belt 14 and the driving roller around which the belt 14 is stretched. And a driven roller (not shown), and a driving means (not shown) for rotating and driving the driving roller. The containers 3 are sequentially loaded on the belt 14 and transported.

In the ultrasonic radiation device 1, an ultrasonic vibration generator 17 (see FIG. 1) is connected to the vibration plate 7. The ultrasonic vibration generating section 17 is for exciting the diaphragm 7, and as shown in FIG. 1, a Langevin type vibrator 19 is provided between the vibrator 19 and the vibrating plate 7. And a horn 20 interposed therebetween. The diaphragm 7 is fastened to the tip of the horn 20 by bolts 22 at its main surface, that is, at the center of the vibration surface.

As shown in FIG. 1, an oscillator 24 is connected to the vibrator 19, and is driven by a high-frequency voltage applied from the oscillator 24 to emit ultrasonic waves. The oscillator 24 and the ultrasonic vibration generator 17 are collectively referred to as ultrasonic excitation means. As shown by an arrow U in FIG. 1, the vibration generated by the vibrator 19 is a longitudinal vibration. The horn 20 has a conical portion 20a and a straight portion 20b, and the vibration amplifying action is performed by the conical portion 20a.

The conical portion 20a and the vibrator 19 of the horn 20 are surrounded by a case 26. The case 26 has a case body 26a and a lid 26c fastened to the case body 26a by bolts 26b. I have. The conical portion 20a of the horn 20 is formed with a flange 20c at a nodal point, and the horn 20 is mounted on the lid 26c of the case 26 via the packing 28 at the flange 20c.

In the ultrasonic radiation device 1 having the above configuration,
Based on the longitudinal vibration transmitted through the horn 20, the vibration plate 7 bends and vibrates in its length direction and width direction. In other words, a planar vibration mode is obtained. Due to this vibration, ultrasonic waves are emitted from both sides of the diaphragm 7.

The ultrasonic radiating device 1 includes a sound field forming means 30 for changing the direction of a sound wave emitted from the diaphragm and forming a sound field having a linear sound wave focal point. The sound field forming means 30 includes parabolic reflectors 31 and 32 disposed on the front side and the rear side of the diaphragm 7, respectively, and a plurality of parabolic reflectors 31 disposed on the parabolic reflector 31 at equal intervals. Partition plate 3
3 and a plurality of partition plates 34 similarly arranged on the other parabolic reflector 32 at equal intervals. Here, these two parabolic reflectors 31 and 32 are formed in substantially the same shape as each other, and are formed slightly longer than the diaphragm 7. On the other hand, each of the plurality of partition plates 33 is positioned at a position corresponding to a node portion of the vibration mode of the diaphragm 7 in a stripe shape,
Similarly, each of the plurality of partition plates 34 is also positioned at a position corresponding to a node portion of the diaphragm 7 in the striped vibration mode.

The parabolic reflectors 31, 32 are not in contact with the diaphragm 7 and the horn 20. Therefore, in the parabolic reflector 32 in which the horn 20 penetrates, an insertion hole 32a through which the horn 20 is inserted with a gap is formed.

The materials of the parabolic reflectors 31 and 32 are as follows:
Those that effectively reflect without absorbing ultrasonic waves are selected. In the case of the present embodiment, duralumin or the like is used as in the case of the diaphragm 7. The parabolic reflectors 31 and 32 are fixed to a fixing member (not shown).

[0028] In the sound field forming unit 30 having the above configuration, the sound wave emitted toward the upper direction as shown from the front side of the vibration plate 7 by the arrow a _1, as indicated by arrow a _2, parabolic reflector The light is reflected by 31 and is redirected, traveling substantially in the horizontal direction, and passing through a linear sound wave focal point coincident with the x-axis (FIG. 1).

Further, sound waves emitted toward the downward direction from the rear side of the diaphragm 7 as shown by the arrow b _1, the arrow b ₂
As shown by, the direction is changed by being reflected by the parabolic reflector 32, is directed substantially in the horizontal direction, and passes through a linear sound wave focal point coincident with the x-axis.

In the vicinity of a linear sound wave focal point coincident with the x-axis,
The mouth 3a of the container 3 is located, and the bubbles that are about to overflow from the mouth 3a of the container 3 disappear very quickly by receiving the ultrasonic waves.

As described above, in the ultrasonic wave radiating apparatus 1, the sound field formation that changes the direction of the sound wave in all directions of the diaphragm 7 and forms a sound field having a linear sound wave focal point (x-axis) is performed. Means 30 are provided. Therefore, the vibration energy generated from the back side of the vibration plate 7, that is, the side where the ultrasonic excitation means is located, also effectively acts on the bubbles, and furthermore, the vibration energy is generated by forming a sound field having a linear sound wave focal point. It is possible to improve the use efficiency of the device.

Accordingly, the work efficiency for erasing bubbles is increased, and the power consumption is suppressed without wasting energy, and the cost is reduced.

The two parabolic reflectors 31, 32 are
It may be one.

FIG. 3 shows a resonance frequency of 19.5 kHz, a length of 42.0 cm, and a width of 12.8 as the ultrasonic radiation device 1.
7A shows the measurement results of a prototype using the diaphragm 7 cm, (A) shows a sound pressure distribution on the y-axis, (B) shows a sound pressure distribution on the z-axis, and (C) shows a sound pressure distribution on the x-axis. It is a sound pressure distribution. From these measurement results, on the y-axis, about 1
The maximum value of the sound pressure appears at a position of 7.5 cm, and the maximum value of the sound pressure appears on the z-axis at a position where the distance from the y-axis is “0 cm”, that is, at a position coinciding with the y-axis, and on the x-axis. In
It was found that the sound wave was focused in the same range as the length of the diaphragm 7 (about 40 cm in length), and that a sound field having a linear sound wave focus was formed on the x-axis.

FIG. 4 is a sectional view of an ultrasonic radiation device according to a second embodiment of the present invention, and FIG. 5 is a schematic perspective view of the device and a conveyor.

The ultrasonic radiating device 1 according to the second embodiment is used as a foam erasing device for eliminating bubbles overflowing in the head space of a container filled with beer or the like, as in the first embodiment.

The ultrasonic radiating apparatus 1 according to the second embodiment is similar to the first embodiment, except that two parabolic reflectors 31 and 32 provided with partitioning plates 33 and 34 are additionally provided. The sound field forming means 30 is constituted by adding a plane reflector 35, and the sound wave whose direction has been changed in a substantially horizontal direction by the parabolic reflectors 31 and 32 is further directed in a substantially downward direction by the plane reflector 35. To form a sound field having a linear sound wave focal point coincident with the x ′ axis (FIG. 4, the plane reflector 35 has a symmetrical relationship with the x axis (FIGS. 1, 4)). It is characterized by having. Here, the flat reflecting plate 35 forms a predetermined angle, for example, 45 ° with respect to the diaphragm 7.
This angle is not limited to 45 °, and may be any angle that can form a sound field having a linear sound wave focal point.

The material of the flat reflector 35 is the same as that of the parabolic reflectors 31 and 32, and the length thereof is set substantially equal to that of the parabolic reflectors 31 and 32. In addition,
Other configurations are the same as those in the first embodiment, and are denoted by the same reference numerals as those in the first embodiment.

In the sound field forming means 30 in the second embodiment, a sound wave emitted upward from the front side of the diaphragm 7 as shown by the arrow a ₁ is expressed by the arrow a ₂ as shown by the arrow a ₂ .
The direction is changed by being reflected by the parabolic reflector 31,
It is directed substantially horizontally and attempts to focus on a linear acoustic focus that coincides with the x-axis (FIG. 4). However, due to the presence of flat reflector 35 in front of the acoustic wave, the acoustic wave direction is changed to the substantially horizontal direction are reflected by a plane reflecting plate 35, as indicated by an arrow a _3, to substantially lower The direction is changed so that it passes through a linear acoustic focus that coincides with the x 'axis.

The sound wave emitted downward from the back side of the diaphragm 7 as shown by the arrow b ₁ is the arrow b ₂
As shown by, the direction is changed by being reflected by the parabolic reflector 32, and is directed substantially in the horizontal direction.
It is changed the direction to substantially downward as shown by an arrow b ₃ makes to pass through the linear sound wave focus coincident with x 'axis.

The mouth 3a of the container 3 is located near the linear sound wave focal point coincident with the x 'axis, and the bubbles overflowing from the mouth 3a of the container 3 receive the ultrasonic waves and become extremely It disappears quickly.

As described above, in the ultrasonic wave radiating device 1 according to the second embodiment, the direction of the sound wave in all directions of the diaphragm 7 is changed, and the sound field having a linear sound wave focal point (x 'axis) is formed. A sound field forming means 30 to be formed is provided. Therefore,
As in the first embodiment, the vibration energy generated from the back side of the diaphragm 7, that is, the side on which the ultrasonic excitation means is located, also effectively acts on the bubbles, and has a sound field having a linear sound wave focal point. Can improve the efficiency of use of vibration energy.

6 and 7 show the measurement results of a prototype using the diaphragm 7 having a resonance frequency of 19.5 kHz, a length of 42.0 cm and a width of 12.8 cm as the ultrasonic wave radiating device 1. FIG. 6A shows a sound pressure distribution on the x ′ axis, and FIG.
(B) shows the sound pressure distribution on the y 'axis, and FIG. 7 shows the relationship between the supplied power and the sound pressure of the sound field. From these measurement results,
On the x 'axis, a sound pressure distribution substantially similar to that in FIG. 3C is obtained, and on the y' axis, a sound pressure distribution slightly different from that in FIG. And
Further, it was found that the sound pressure was increased in the relation of about 1/2 of the supplied power, and that a strong sound field of about 162 dB was obtained at a supplied power of about 70 W.

Further, when a defoaming experiment (sound pressure of a sound wave applied to the foam was about 160 dB) was performed using the prototype ultrasonic radiation device, it was found that a defoaming effect almost as expected could be expected.

[0045]

The ultrasonic wave radiating device of the present invention comprises sound field forming means for changing the direction of sound waves in all directions of the diaphragm to form a sound field having a linear sound wave focal point. Even when a mechanical part such as a diaphragm is damaged, no foreign matter is mixed into the product, stable operation for a long time can be secured, and work efficiency can be improved. Further, since the ultrasonic wave radiating device of the present invention forms a linear sound wave focal point, even relatively large bubbles remaining in the container, for example, bubbles having a diameter of 1 mm or more, can be reliably eliminated. As a result, there is no possibility that the product is oxidized by oxygen in the air and the quality is deteriorated. In addition, since the bubbles can be reliably eliminated, there is no variation in the internal volume of the product and the removed bubbles do not scatter around the product, which is hygienic.

[Brief description of the drawings]

FIG. 1 is a sectional configuration diagram of an ultrasonic radiation device according to a first embodiment.

FIG. 2 is a schematic perspective view of the apparatus and a conveyor.

FIG. 3 is a graph showing measurement results of a prototype of the apparatus.

FIG. 4 is a cross-sectional configuration diagram of an ultrasonic radiation device according to a second embodiment.

FIG. 5 is a schematic perspective view of the apparatus and a conveyor.

FIG. 6 is a graph showing measurement results of a prototype of the same device.

FIG. 7 is a graph showing measurement results of a prototype of the same device.

FIG. 8 is a front view of a first conventional bubble elimination device.

FIG. 9 is a view showing a vibration mode of a diaphragm of the same device.

FIG. 10 is a side view of a second conventional bubble eliminating device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ultrasonic radiation device 7 Vibration plate 17 Ultrasonic vibration generation part (ultrasonic excitation means) 24 Oscillator (ultrasonic excitation means) 30 Sound field forming means 31, 32 Parabolic reflector 33, 34 Partition plate 35 Flat reflector

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Yoshiki Hashimoto 3-1-5 Sakaemachi, Hamura City, Tokyo Inside Kaijo Co., Ltd.

Claims (6)

[Claims] 1. A diaphragm, an ultrasonic exciting unit for exciting the diaphragm, and a sound field forming device for changing a direction of sound waves in all directions of the diaphragm to form a sound field having a linear sound wave focal point And an ultrasonic radiation device. 2. The ultrasonic radiation device according to claim 1, wherein said sound field forming means comprises a parabolic reflector. 3. The vibration plate is provided so as to generate a sound wave going up and down, and the parabolic reflector reflects the sound wave going up and down and goes to a first linear sound wave focal point. 3. The ultrasonic radiation device according to claim 2, wherein the direction of the sound wave is changed in a horizontal direction. 4. The ultrasonic radiating apparatus according to claim 1, wherein said sound field forming means comprises a parabolic reflector and a plane reflector. 5. The vibration plate is provided so as to generate a sound wave going up and down, and the parabolic reflector reflects the sound wave going up and down toward a first linear sound wave focus. So that the direction of the sound wave is changed in the horizontal direction, and the plane reflector reflects the sound wave directed to the first sound wave focus, and changes the direction of the sound wave downward so as to be directed to the linear second sound wave focus. The ultrasonic radiation device according to claim 4, wherein the ultrasonic radiation is performed. 6. The super-parameter according to claim 2, wherein a partition plate is provided on the parabolic reflector in correspondence with a vibration mode of the diaphragm. Sound emitting device.