JP2866768B2 - Ultrasonic cleaning machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic cleaner for radiating ultrasonic waves into a cleaning liquid to clean the surface of an object to be cleaned in the cleaning liquid.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 2, an ultrasonic cleaning machine of this type has an ultrasonic cleaning device which is fixed on a lower surface of a bottom wall 1a of the cleaning bath 1 and driven by an oscillation unit (not shown). A basic structure including a vibrator 2, a base 3 supporting the cleaning tank 1, and a drain 4 opened at the bottom of the cleaning tank 1 is provided. The object W to be cleaned is immersed in the cleaning liquid 5 injected into the cleaning tank 1, and the ultrasonic vibrator 2 is excited to emit ultrasonic waves into the cleaning liquid 5, whereby the stirring action and cavitation generated in the cleaning liquid 5 are caused. By the action, contaminants such as oils and fats adhering to the surface of the cleaning object W are quickly and completely peeled and removed.

[0003] When a solvent is washed using an acidic or alkaline solvent or an organic solvent as the washing liquid 5, the washing tank 1 is corroded by such a solvent in a normal tank made of stainless steel. For this reason, for example, PV
Either a synthetic resin having excellent solvent resistance such as DF (polyvinylidene fluoride) or the like is used. Alternatively, as shown in FIG. An inner tank 6 such as a beaker filled with the cleaning liquid 5 is immersed in water, and the object W to be cleaned is washed in the inner tank 6.

[0004]

According to the above prior art, when the cleaning tank 1 is made of a synthetic resin such as PVDF,
There is a problem in the bonding strength between the lower surface of the bottom wall 1a and the ultrasonic vibrator 2, and the temperature rise (about 60 ° C. or more) due to continuous excitation of the ultrasonic vibrator 2 for a long time causes the bottom wall 1a. There is a case where the adhesion portion between the ultrasonic transducer 2 and the ultrasonic transducer 2 is peeled off. For this reason, it is difficult to control the temperature of the cleaning liquid 5 and the temperature of the bonding portion, and it is difficult to increase the output for the purpose of increasing the cleaning power. In addition, if peeling occurs in the bonded portion, it is difficult for the user to perform the bonding again.
The entire cleaning tank 1 needs to be transported to a factory for repair (replacement / adhesion of the vibrator, etc.), which raises a problem that maintenance costs rise.

On the other hand, in the conventional cleaning method shown in FIG. 3, since the cleaning is performed in the inner bath 6, there is a problem that the size of the object W to be cleaned is significantly restricted. 1
The contact surface between the a and the glass container 6 may generate heat due to friction or the like accompanying vibration. In this case as well, the adhesive layer between the bottom wall 1a and the inner tank 2 is softened or deteriorated, and the ultrasonic transducer 2 is separated.・ It may fall off. Further, due to the movement of the inner tub 6, bubbles are generated by cavitation between the bottom surface 6a of the inner tub 6 and the bottom wall 1a of the cleaning tub 1, and the vibration energy transmitted from the bottom wall 1a to the inner tub 6 side. In addition, the cleaning power is significantly reduced, the cleaning power is reduced, the bottom wall 1a of the cleaning tank 1 is eroded (erosion), and the ultrasonic vibrator 2 is excited in a light load state to shorten the life. is there.

The present invention has been made in view of the above-mentioned problems of the prior art, and its main object is to prevent peeling of an ultrasonic vibrator due to temperature rise during long-time operation. An object of the present invention is to facilitate repair in the case where peeling has occurred, and to improve the cleaning power and the service life.

[0007]

An ultrasonic cleaner according to the present invention which solves the above-mentioned problems of the prior art has a cleaning tank formed on the upper side via a partition and a side wall surface of the liquid filling chamber on the lower side. And a tank body made of a solvent-resistant material forming the tank body, and detachably attached to the lower end of the side wall surface of the liquid filling chamber at the upper part of the base holding the tank body while maintaining the liquid tightness with the lower end. And an ultrasonic vibrator fixed on the lower surface of the vibrating plate.

A preferred embodiment of the present invention is provided with a supply / drainage mechanism for circulating the sealed liquid in the liquid sealing chamber.

[0009]

According to the structure of the present invention, a cleaning liquid such as water or an acidic solvent is injected into the upper cleaning tank of the solvent-resistant tank main body, and water is injected into the liquid sealing chamber having the diaphragm sealed at the lower end. The ultrasonic wave generated by driving the ultrasonic vibrator is radiated from the diaphragm to the cleaning liquid in the cleaning tank through the sealing liquid in the liquid charging chamber and the partition wall, and immersed in the cleaning liquid. It has a cleaning effect on the surface of the object to be cleaned. In this case, the diaphragm, the thickness of the partition wall, and the depth of the sealed liquid layer between the diaphragm and the partition wall are based on the sound speed of the ultrasonic wave in each material, and are approximately half the wavelength of the ultrasonic wave at the working frequency or its half. By setting so as to be an integral multiple, propagation of ultrasonic energy in the cleaning tank is most efficiently performed.

According to a preferred embodiment of the present invention,
The liquid in the liquid filling chamber is supplied from the outside through the liquid supply port, and is discharged from the liquid discharge port to the outside and constantly circulated, so that the heat generated in the bonding portion between the ultrasonic vibrator and the diaphragm and the cleaning tank is generated. Is efficiently removed.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an ultrasonic cleaner according to the present invention will be described with reference to a preferred embodiment shown in FIG. 1. First, reference numeral 10 indicates a tank body, and a side wall 11 and a height direction thereof. It has a substantially H-shaped cross section composed of a substantially horizontal partition wall 12 in the middle abdomen. An upper cleaning tank 10A having an open upper end and a lower liquid enclosing chamber 10B having an open lower end are interposed through the partition wall 12. It is defined. The tank body 10 is typically formed of PVDF (polyvinylidene fluoride) having excellent solvent resistance, but may be formed of, for example, nylon, polyvinyl chloride, polyethylene, polypropylene, or ABS.
A synthetic resin material such as a resin can be used.

Reference numeral 13 denotes a diaphragm made of a metal such as stainless steel. The base plate 15 is attached to the lower end opening of the liquid filling chamber 10B, that is, the lower end 11a of the side wall 11 via an elastomer packing 14. The upper and lower flange portions 15a are detachably sealed together with a plurality of screw members 16, and a piezoelectric effect type or magnetostrictive effect type ultrasonic vibrator excited by an oscillating portion (not shown) is provided on the lower surface of the diaphragm 13. 17 are firmly bonded via an adhesive. The diaphragm 13 may be made of the same material as the tank body, in addition to the metal such as stainless steel.

The diaphragm 13 has a liquid supply port 18 communicating with the bottom of the liquid filling chamber 10B, and the side wall 11 of the tank body 10 has a liquid discharging port communicating with the upper part of the liquid filling chamber 10B. Exit 19 is open. 18a, 19
a is a shutoff valve provided at each of the liquid supply port 18 and the liquid discharge port 19. In addition, the liquid supply port 18 can be opened at the lowermost portion of the side wall 11 of the tank body 10.

A method of cleaning the surface of the cleaning object W using the ultrasonic cleaning machine of the present embodiment having the above-described configuration will be described. The cleaning tank 10A in the tank body 10 contains water or an acidic solvent. The cleaning liquid L1 is injected to an appropriate liquid level, for example, a liquid level corresponding to a half wavelength of the ultrasonic wave radiated from the ultrasonic vibrator 17 or an integral multiple thereof.
In the liquid filling chamber 10B, the liquid supply port 18 is connected to an external city water supply means and the liquid discharge port 19 is opened, or the liquid supply port 18 and the liquid discharge port 19 are connected to a liquid circulation (not shown). By connecting to the supply device, the city water L2 is completely filled and constantly recirculated.

When the ultrasonic vibrator 17 is excited in this state, the vibrating plate 13 adhered thereto resonates, and ultrasonic waves are radiated from the upper surface into the city water L2 sealed in the liquid sealing chamber 10B. Further, it is transmitted through the partition wall 12 to the cleaning liquid L1 in the cleaning tank 10B. The thickness t2 of the diaphragm 13
The height h of the inner wall of the liquid enclosing chamber 10B, the thickness t1 of the partition wall 12, and the level of the cleaning liquid L1 in the cleaning tank 10A are respectively a half wavelength of the ultrasonic wave or an integer (including zero) times the half wavelength. Set to approximately equal values.

Thus, the ultrasonic waves radiated from the ultrasonic vibrator 17 are transmitted to the interface between the diaphragm 13 and the city water L2 in the liquid filling chamber 10B, the interface between the city water L2 and the partition wall 12, the partition wall 12 and the like.
There is a standing wave having an antinode of a waveform at the interface between the cleaning liquid L1 and the liquid surface of the cleaning liquid L1, so that a sound field where the change in sound pressure is maximized at these portions is formed. As an example,
The thickness t2 of the diaphragm 13 and the thickness t1 of the partition 12 are set to almost zero times the half wavelength, that is, a value sufficiently smaller than the half wavelength.

At the bonding portion between the ultrasonic vibrator 17 and the vibrating plate 13 and at the portion where the change in sound pressure is maximum in the cleaning tank 10B or the like, some heat is generated due to friction. In the enclosing chamber 10B, the city water L2 is constantly circulated from the outside, and is efficiently removed to the outside by the heat exchange action. Therefore, it is possible to effectively avoid a situation in which the adhesive interposed between the vibration plate 13 and the ultrasonic vibrator 17 softens or deteriorates and peels off.

Since the ultrasonic vibrator 17 is bonded to the vibrating plate 13 made of stainless steel, the ultrasonic vibrator 17 is bonded to the bottom surface of the cleaning tank made of PVDF or integrated with the bottom surface when the cleaning layer is formed. The production cost is lower than in the conventional case, and the adhesive strength can be sufficiently improved. In addition, even in the event that the ultrasonic vibrator 17 is separated or dropped from the vibration plate 13, the vibration plate 13 can be moved by simply loosening the screw member 16.
Since the vibration plate 13 can be easily removed at the site of use because the diaphragm 13 can be easily removed, the repair becomes easy, and the cost required for it can be reduced.

The tank body 10 including the cleaning tank 10A is
Since it is made of a material having excellent solvent resistance, there is no need to use an inner tank as in the case of a stainless steel tank. Therefore, not only is the restriction on the size of the object W to be cleaned relieved, but also the phenomenon that bubbles generated by cavitation when using the inner tank attenuates ultrasonic energy cannot occur, thereby improving the cleaning power. In addition, the ultrasonic vibrator 17 is not driven in a low load state due to erosion generated in the partition wall 12.

In the above configuration, the liquid supply port 1
8 and the opening position or opening direction of the liquid discharge port 19 are as follows:
The number and arrangement of the ultrasonic vibrators 17 are appropriately determined in consideration of the formation of a stagnant portion of the city water L2 and the formation of an air pocket in the liquid filling chamber 10B. The liquid to be filled into the liquid filling chamber 10B is not particularly limited to the city water L2.

[0021]

As is apparent from the above description, the ultrasonic cleaner according to the present invention has the following effects. (1) When a solvent is used as the cleaning solution, there is no need to immerse the object to be cleaned in the inner tank into which the cleaning liquid has been injected. This can prevent a reduction in cleaning power, generation of erosion, and shortening of the life of the ultrasonic vibrator due to low load driving. (2) Since the diaphragm can be easily removed from the tank main body, repairs when the ultrasonic vibrator peels off are easy, and the cost required for the repair can be reduced. (3) Since the liquid as the ultrasonic transmission medium flows through the liquid enclosing chamber, a rise in temperature during driving is suppressed, and deterioration of the material is prevented.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing one embodiment of an ultrasonic cleaner according to the present invention.

FIG. 2 is a schematic cross-sectional view illustrating an example of an ultrasonic cleaning machine according to the related art.

FIG. 3 is a schematic cross-sectional view showing another example of the ultrasonic cleaning machine according to the related art.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Tank main body 10A Cleaning tank 10B Liquid filling chamber 11 Side wall 12 Partition 13 Vibrating plate 14 Packing 15 Base 16 Screw member 17 Ultrasonic vibrator 18 Liquid supply port 19 Liquid discharge port

Claims (3)

(57) [Claims] 1. A solvent-resistant solvent having a cleaning tank formed on the upper side and a side wall surface of a liquid filling chamber formed on a lower side via a partition.
H-shaped cross section made of PVDF or other organic material
A diaphragm which is detachably screwed to a lower end of a side wall surface of the liquid sealing chamber at an upper portion of a base holding the bath main body while maintaining liquid tightness with the lower end; An ultrasonic cleaner, comprising: an ultrasonic vibrator bonded and fixed to a lower surface of a plate. 2. The ultrasonic cleaning machine according to claim 1, further comprising a supply / drainage mechanism for circulating the enclosed liquid in the liquid enclosure. 3. The liquid-filled chamber according to claim 1 , wherein the height of the liquid-filled chamber is determined by an ultrasonic wave propagating through the chamber.
Characteristically set to be approximately half-wavelength value
Ultrasonic cleaning machine .