JPS6327826Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a processing tank using ultrasonic waves, particularly a cleaning tank used in an ultrasonic cleaning device.
Using an ultrasonic transducer with a special structure, it is possible to generate ultrasonic waves of multiple frequencies or to synthesize ultrasonic waves with different directivity as necessary.

As shown in FIG. 1, when ultrasonic waves are generated in the cleaning liquid 3 from the ultrasonic transducer 2 disposed at the bottom of the tank 1, a standing wave as shown by the curved line is generated inside the liquid.
If the wavelength is λ, then from the liquid level λ/4, 3λ/4, 5λ/4...
The cleaning effect is maximum at the point where the vibration amplitude is maximum, and the points at λ/2, λ, 3λ/2,
In other words, it is minimum at the point corresponding to the amplitude node.

Therefore, when the object to be cleaned is put into the tank and washed, the cleaning effect is significantly different between the abdomen and the joints, resulting in uneven cleaning.

Therefore, in order to remove these inconveniences and perform even cleaning, conventionally a stirring device was used to move the object to be cleaned over a range of 1/4 wavelength or more, and mechanical movements such as vertical movement or horizontal rocking were used. However, the disadvantage was that the stirring device was complicated and expensive.

Instead of moving the object to be cleaned using such mechanical means, the present invention uses a vibrator shaped to generate ultrasonic waves with multiple resonance frequencies with different vibration modes, and the positions of the antinodes and nodes are It creates different vibrations in the tank and cleans the entire surface of the object to be cleaned evenly.

By the way, ultrasound is used in all fields such as physics, chemistry, engineering, medicine, and biology.
In most cases, the frequency ranges over a wide range from about 10 KHz to about 10 MHz, but since the expected effects differ depending on the target, a frequency suitable for each must be selected.

Taking cleaning as an example, relatively low frequencies (10~
50KHz) range is suitable for removing dust, and high frequency (100KHz or higher) seems to be good for degreasing.

Therefore, generating different frequencies is not only effective in eliminating the effects of standing waves and eliminating uneven cleaning, but also can be used in various applications where good results can be obtained using different frequencies. It opens the way.

Next, description will be given with reference to examples.

FIG. 2 is a side view showing a part of the embodiment in section;
FIG. 3 is a bottom view. Two transducers, a ring-shaped transducer 5 and a disk-shaped transducer 6, are fixed to the outside of the bottom surface of the tank 1 with adhesive A. Each transducer is configured to emit ultrasonic waves into the cleaning liquid 3, and the two are arranged in the same center with a gap 7 between them.

The annular vibrator 5 has an outer diameter as shown in FIG.
2r, height l, and thickness t, and a vibrator constructed in this way generally has three different modes of vibration regarding radius, thickness, and width, as shown in Figure 4 (b). It has resonant frequencies _r , _l and _t . For example, r=3cm, l=3cm, t=0.5
If cm, _r = 20KHz, l = 60KHz, _t = 500K
Hz is obtained. Regarding the disk vibrator 6,
Needless to say, vibration in the radial direction and vibration in the thickness direction can be obtained.

Thus, the present invention can be constructed by combining the annular vibrator 5 and the disk vibrator 6 to generate ultrasonic waves having different resonance frequencies, which eliminates uneven cleaning, allows multipurpose use, and significantly simplifies the structure. , it has the advantage of not taking up much space and significantly reducing costs. It is also possible to combine materials with different resonance frequencies. other,
Focusing on directivity, when the central disk vibrator and the ring vibrator surrounding it are vibrated through their thickness,
Since a disk vibrator has a wide directivity, and an annular vibrator has a narrow directivity, a desired directivity can be combined by selecting the dimensions.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of an ultrasonic cleaning tank. FIG. 2 is a surface measurement diagram of an embodiment of the present invention. FIG. 3 is a bottom view of the embodiment of the present invention. Figure 4 is an explanatory diagram of the annular vibrator and its resonance characteristics. 1... Bath, 2... Ultrasonic vibrator, 3... Cleaning liquid, 4... Adhesive, 5... Annular vibrator, 6...
Disc oscillator, 7... air gap.

Claims (1)

[Scope of utility model registration request] A set of ultrasonic transducers is formed by a disc-shaped transducer and a hollow cylindrical annular transducer sandwiching the transducer at a certain interval, and these are attached to the bottom of the tank. An ultrasonic treatment tank characterized by: