JPH0839025A - Cleaning method - Google Patents

Abstract

PURPOSE:To control the lowering of ultrasonic cavitation effect and prevent the re-adhesion of floating soils. CONSTITUTION:A ultrasonic oscillator 2 is set on the bottom section of a cleaning tank 1. Cleaning fluid is circulated between the cleaning tank 1 and a reserve tank 3 by a circulating pump 4 and overflowed. The circulating amount of cleaning fluid is set so as to satisfy the equation [circulating amount of cleaning fluid (l/minute)]/[cleaning tank volume (liter)]=0.1-0.4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ultrasonic cleaning effect and a cleaning liquid for cleaning oils and fats such as cutting oil, adhesives, hand grease, dust, etc. adhering to parts such as metal, glass, ceramics and plastics. The present invention relates to a cleaning method capable of efficiently cleaning in a short time by utilizing the circulation / overflow mechanism of

[0002]

2. Description of the Related Art Generally, ultrasonic waves are used as an auxiliary means for increasing cleaning efficiency in cleaning for removing cutting oil, machine oil, hand oil, dust, etc. adhering to parts such as metal, glass and ceramics. It is being cleaned. And
During cleaning, the cleaning liquid in the cleaning tank normally overflows and is stored in the spare tank. The cleaning liquid stored in the spare tank is pumped by a pump to remove dust through a filter, and then returned to the cleaning tank again to circulate the cleaning liquid.

In order to carry out the cleaning efficiently in a short time, a method using ultrasonic waves has been adopted. However, in most cleaning methods, the cavitation effect of ultrasonic waves is attenuated and the cleaning effect by ultrasonic waves is sufficient. Not obtained. Therefore, in order to increase the cleaning power, as disclosed in Japanese Patent Laid-Open No. 4-199714, the frequency of ultrasonic waves is changed, or the depth of the cleaning liquid is changed in synchronization with the change in oscillation frequency of ultrasonic waves. The way is done.

When the object to be cleaned is pulled out from the cleaning tank, in order to prevent re-adhesion of oil floating on the liquid surface,
A method of overflowing the cleaning liquid to remove dirt such as oil floating on the liquid surface is generally used. Japanese Unexamined Patent Publication No. 5-92186 discloses a method in which pressurized air is jetted from the negative side of the cleaning tank toward the liquid outflow side (overflow side) to force the floating oil or the like to overflow. .

[0005]

However, in the ultrasonic cleaning, when the cleaning liquid is circulated by using a pump, a turbulent flow of the cleaning liquid occurs in the cleaning tank, so that the cavitation effect of the ultrasonic waves is significantly reduced. As a result, a sufficient cleaning effect cannot be obtained.

The method used in Japanese Patent Laid-Open No. 4-199714 attempts to prevent the cavitation effect of ultrasonic waves from being lowered by changing the frequency of ultrasonic waves or changing the depth of the liquid in synchronization. However, it is not practical considering the complexity of the device, the complexity of the work, and the cost increase. Further, if the cleaning liquid is circulated and does not overflow, dirt such as oil floats on the surface of the cleaning liquid, so that the dirt is redeposited when the object to be cleaned is pulled out from the cleaning tank. Therefore, in the method used in Japanese Patent Laid-Open No. 5-92186, pressured air is jetted from the-side of the cleaning tank toward the liquid outflow side (overflow side) to forcibly suspend floating oil and the like. It is overflowing. But,
In this method, when the object to be cleaned is pulled out of the cleaning liquid, the pressurized air directly hits the object to be cleaned, so that the object to be cleaned is dried, the components of the cleaning liquid are dried and solidified on the object to be cleaned, and stains are formed on the object to be cleaned. There is a problem that problems such as the above occur. Further, with this method, although the dirt floating on the surface of the cleaning liquid can be removed to some extent, it is not perfect and is not mixed with the cleaning liquid, so that emulsification and dissolution are difficult.

The present invention has been made in view of the above-mentioned conventional problems, and the invention according to claim 1 has an overflow function of the cleaning liquid for defining the circulation amount of the cleaning liquid and preventing reattachment of dirt. However, it is an object of the present invention to provide a cleaning method capable of suppressing deterioration of the cavitation effect of ultrasonic waves.

According to the second aspect of the invention, the ultrasonic effect is maximized by stopping the circulation of the cleaning liquid while the ultrasonic waves are being output and the cleaning is performed. An object of the present invention is to provide a cleaning method capable of preventing reattachment of floating dirt by circulating a cleaning liquid immediately after immersion and immediately before completion of cleaning.

According to the third aspect of the present invention, since a large amount of dirt is carried in and a large amount of dirt floats on the liquid surface, when it is necessary to forcibly overflow the cleaning liquid at all times, the cavitation effect of ultrasonic waves is reduced. An object of the present invention is to provide a cleaning method that can suppress and prevent redeposition of dirt.

That is, the circulation amount of the cleaning liquid as described above,
A cleaning method that enhances the cleaning effect by ultrasonic waves and provides sufficient cleaning quality by using a liquid circulation method and a cleaning liquid supply method.

[0011]

In order to solve the above problems, the invention according to claim 1 provides a cleaning method in which cleaning is performed using ultrasonic waves, wherein the circulating amount of the cleaning liquid is [circulating amount of cleaning liquid (liter / liter / Min)] / [washing tank capacity (liter)] = 0.1 to 0.4.

According to the second aspect of the present invention, in the cleaning method using ultrasonic waves, intermittent circulation is performed to stop the circulation of the cleaning liquid while the object to be cleaned is being cleaned.

The invention according to claim 3 is characterized in that the cleaning liquid is uniformly dispersed and supplied in a horizontal direction and a vertically downward direction at a position within 100 mm below the surface of the cleaning liquid in the cleaning tank. Is the way.

[0014]

The operation of the invention according to claim 1 is that, as the circulation amount of the cleaning liquid, the ratio of the circulation amount of the cleaning tank is [the circulation amount of the cleaning liquid (liter / minute)] / [the cleaning tank volume (liter)] = 0. 0.1 to 0.4 and control the circulating amount of the cleaning liquid to perform cleaning without lowering the cavitation effect of ultrasonic waves. Further, at this time, when the circulating cleaning liquid is supplied into the cleaning tank, a dispersion plate or the like is provided at the supply port so that the supplied cleaning liquid does not directly contact the object to be cleaned, and the cleaning liquid is dispersed and supplied, thereby further It is possible to suppress deterioration of the cavitation effect of sound waves.

In the invention according to claim 2, the circulation of the cleaning liquid is stopped by the ON / OFF control of the circulation pump while the object to be cleaned is immersed in the cleaning tank (at the time of ultrasonic oscillation). By stopping the circulation of the cleaning liquid, the turbulent flow of the cleaning liquid in the cleaning tank is eliminated, the cavitation effect of ultrasonic waves is enhanced, the original effect of ultrasonic cleaning is exerted, and the cleaning performance is improved. As a specific example of this intermittent circulation method, the cleaning liquid is circulated from immediately before the completion of cleaning (within 120 seconds) to a fixed time (within 120 seconds) after the next object to be cleaned, and in other cases, circulation of the cleaning liquid. And so on. As a result, the effect of ultrasonic cleaning is exerted while the retention function of the cleaning liquid in the cleaning tank and the overflow function of the cleaning liquid (prevention of reattachment of floating dirt) are exerted, and the cleaning property is improved. At this time, even if the ultrasonic waves are constantly oscillating,
It may oscillate only when the object to be cleaned enters the cleaning tank.

The effect of the invention according to claim 3 is that, when dirt is heavily mixed from the object to be cleaned and it is necessary to constantly circulate the cleaning liquid, as shown in FIG. By directing the jet of water from within 100 mm below the liquid surface in both the horizontal and vertical downward directions, it is possible to prevent the cavitation effect of ultrasonic waves in the cleaning tank 1 from decreasing while forcibly overflowing the floating dirt. The function is to replace the cleaning liquid in the cleaning tank 1 and prevent the liquid from staying.

By forcibly overflowing with the circulating cleaning liquid, the floating dirt can be efficiently removed in a short time, and reattachment to the object to be cleaned can be prevented. At this time, the cleaning liquid discharged in the horizontal direction and the vertically downward direction may be dispersed and jetted so as to spread over the entire surface of the cleaning tank, and it is more efficient to make the overflow area as wide as possible over the entire liquid surface. According to this method, it is possible to enhance the cleaning effect at a low cost without drying the object to be cleaned or requiring a special device such as pressurized air to affect the object to be cleaned. The cleaning liquid used at this time is not limited to an aqueous cleaning liquid and a non-aqueous cleaning liquid, and can be used for all kinds of cleaning liquids.

[0018]

EXAMPLES Next, examples of the present invention will be described with reference to FIGS. FIG. 1 shows a conceptual diagram of a washing machine. In the washing machine shown in FIG. 1, 28 kHz.
The ultrasonic oscillator 2 is installed. The cleaning liquid is circulated between the cleaning tank 1 and the spare tank 3 by the circulation pump 4,
It has the function of overflowing the cleaning liquid.

As the object to be cleaned 5, an optical glass lens and an optical glass prism (glass material BK7, manufactured by Ohara Optical Glass Manufacturing Co., Ltd.) were used so that the presence of minute stains can be visually judged. The washed sample was one that was dipped in cutting oil (Daphne Cut GS90, manufactured by Idemitsu Kosan Co., Ltd.) as stains, and coated with 1.2 mm of a processing adhesive (asphalt pitch K1, manufactured by Kuju Denki KK). Using.

As the cleaning liquid, an aqueous cleaning liquid EE-1120 or a non-aqueous cleaning liquid EE-4110 (both manufactured by Olympus Optical Co., Ltd.) was used.

[Example 1] Table 1 shows the results of confirming the difference in the cleaning effect between the case where the cleaning liquid is constantly circulated and the case where the cleaning liquid is intermittently circulated. The circulation rate of the cleaning liquid was set to 8 liters / minute.

[0022]

[Table 1]

As the intermittent circulation method, the cleaning liquid is circulated and overflowed for 30 seconds after the object to be cleaned is dipped, and then the circulation of the cleaning liquid is stopped. Further, 30 seconds before the completion of cleaning, the cleaning solution was circulated again and overflowed, and then the object to be cleaned was pulled up.

As the cleaning liquid, an alkaline aqueous cleaning liquid EE-
1120 was used. The temperature of the cleaning liquid was set to 30 ° C. The cleaning tank used had a tank capacity of 20 liters.

As the objects to be cleaned, those immersed in cutting oil and the optical glass lens forcibly adhered with hand oil are cleaned,
The degree of cleaning of the lens surface was visually inspected and evaluated (breath test). From this result, the cleaning effect by ultrasonic waves is dramatically improved by stopping the circulation of the cleaning liquid, the lens that causes the stain is almost eliminated, and the stain generated on the lens is extremely thin. Even if you go, problems such as peeling of the coat film do not occur,
A good cleaning quality was confirmed.

However, if the cleaning liquid was not circulated at all, stains such as oil floating on the surface of the cleaning liquid were reattached to the lens surface when the lens was pulled up after the cleaning was completed, and stains due to the residual stain were generated. Therefore, it was confirmed that the cleaning liquid was circulated immediately before the immersion of the object to be cleaned and immediately before it was pulled up, and the cleaning liquid was allowed to overflow, whereby the reattachment of dirt such as floating oil could be prevented.

[Embodiment 2] In order to confirm the cleaning performance by the difference in the circulating amount of the cleaning liquid, the circulating amount of the cleaning liquid was changed between the optical glass lens immersed in cutting oil and the optical glass lens forcibly adhering the hand oil. After cleaning, the degree of cleaning of the lens surface was visually inspected and evaluated (breath test). As the cleaning liquid, an alkaline aqueous cleaning liquid EE-1120 was used. The temperature of the cleaning solution is
It was set to 30 ° C. The cleaning tank used had a tank capacity of 20 liters. Table 2 shows the number of optical glass lenses in which stains and fogging due to residual stains were generated in the evaluation after cleaning.

[0028]

[Table 2]

From this result, by setting the circulating amount of the cleaning liquid to the minimum amount necessary to overflow the floating oil and dirt, the dirt can be prevented from being reattached and the ultrasonic effect can be sufficiently obtained. It was possible to perform cleaning, and it was confirmed that the cleaning performance was improved.

In particular, the circulation rate is 2 liters / minute (circulation rate /
Under the condition of setting the tank volume = 0.1), the degree of stains on the lens is extremely small, and even if coating is performed in the next step, defects such as peeling of the coat film do not occur, and good cleaning quality is confirmed. did.

Similarly, the non-aqueous cleaning liquid EE-4110 was used to confirm the cleaning property of the pitch using an optical glass lens having a pitch K1 of 1.2 mm attached thereto. The cleaning liquid temperature is 4
It was set to 0 ° C. The cleaning tank used had a tank capacity of 20 liters. Table 3 shows the time required for the pitch to be completely cleaned.

[0032]

[Table 3]

From these results, it was possible to carry out the cleaning with a sufficient cavitation effect of ultrasonic waves by setting the circulating amount of the cleaning liquid to the minimum amount, and the pitch could be cleaned in a short time. In particular, in the process of washing in a short time within a constant takt time with a washing machine using an automatic transfer system, the condition that the circulation rate is set to 2 liters / minute (circulation rate / tank volume = 0.1) It was effective.

[Embodiment 3] In order to confirm the cleaning property due to the difference in the supply method of the cleaning liquid, the optical glass prism immersed in a large amount of cutting oil was cleaned.

As the cleaning liquid, an alkaline aqueous cleaning liquid EE-
1120 was used. The temperature of the cleaning liquid was set to 30 ° C. The cleaning tank used had a tank capacity of 20 liters. Table 4 shows the results of visual inspection (exhalation test) for the degree of cleaning of the prism surface.

[0036]

[Table 4]

From these results, when the circulating liquid is directly supplied from near the bottom of the cleaning tank (FIG. 4) and the circulating liquid is supplied vertically and vertically (FIG. 2), the cleaning finish quality is compared. In the latter method, even if a large amount of oil floats on the surface, the circulating fluid is supplied in the horizontal direction of the liquid surface, and the floating oil is forced to overflow, preventing re-adhesion to the object to be cleaned. Good cleaning results were obtained. Further, by discharging the cleaning liquid vertically downward, it is possible to prevent the dirty cleaning liquid from staying in the cleaning tank.

Further, when the circulating cleaning liquid is supplied into the cleaning tank, the cleaning liquid is dispersed by the baffle plate 6 (dispersion plate) so that the cleaning liquid does not directly contact the object to be cleaned. Results were obtained (Fig. 5). this is,
This is because it is possible to perform cleaning with the cavitation effect of ultrasonic waves sufficiently drawn out without disturbing the standing waves of ultrasonic waves.

As for the cleaning quality, the degree of stains generated on the prism was extremely small, and even if coating was performed in the next step, defects such as peeling of the coating film did not occur, and good cleaning quality was confirmed.

From the above results, it is possible to prevent the turbulent flow of the cleaning liquid at the time of supplying the cleaning liquid without disturbing the standing wave of ultrasonic waves, and
It was found that by efficiently removing the floating contaminants by overflow, it is possible to perform cleaning without lowering the effect of ultrasonic waves even when the object to be cleaned to which a large amount of oil has adhered is continuously cleaned.

[0041]

As described above, according to the inventions of claims 1 to 3, by improving the control of the circulating amount of the cleaning liquid, the cleaning liquid circulating method or the cleaning liquid supplying method,
The cavitation effect of ultrasonic waves, which greatly affects the cleaning effect, can be maximized to effectively and efficiently clean the object to be cleaned, and the floating dirt can be removed without reducing the ultrasonic cleaning effect. It is possible to efficiently remove and improve the cleaning property while preventing reattachment of dirt to the object to be cleaned.

[Brief description of drawings]

FIG. 1 is a schematic side view showing a washing machine used in Examples 1 and 2.

FIG. 2 is a schematic side view showing a washing machine used in a third embodiment.

FIG. 3 is a schematic plan view showing a cleaning machine used in a third embodiment.

FIG. 4 is a schematic side view showing another washing machine used in Example 3.

FIG. 5 is a schematic side view showing another washing machine used in the third embodiment.

[Explanation of symbols]

 1 Cleaning tank 2 Ultrasonic oscillator 3 Spare tank 4 Circulation pump 5 Cleaning object

Claims (3)

[Claims] 1. A cleaning method in which cleaning is performed using ultrasonic waves, wherein the circulation amount of the cleaning liquid is [circulation amount of cleaning liquid (liter / min)] / [cleaning tank volume (liter)] = 0.1 to 0.4. A cleaning method comprising: 2. A cleaning method for cleaning using ultrasonic waves, characterized by performing intermittent circulation for stopping the circulation of the cleaning liquid while the object to be cleaned is being cleaned. 3. The cleaning liquid in the cleaning tank is located 100 below the surface of the cleaning liquid.
A cleaning method characterized in that a cleaning liquid is uniformly dispersed and supplied in a horizontal direction and a vertically downward direction at a location within a mm.