JP2000288307A - Deaeration device and ultrasonic washing apparatus equipped therewith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the re-dissolution of gas contained in bubbles generated when a washing soln. used, for example, in an ultrasonic washing apparatus is deaerated under vacuum. SOLUTION: In the deaeration apparatus, a vacuum defoaming cylinder 6 is connected to a vacuum deaeration cylinder 4 on the downstream side of the cylinder 4 and the soap bubble like foam generated in the deaeration cylinder 4 is sent into the defoaming cylinder 6. The level of foam is detected by the level gauge housed in the defoaming cylinder 6 and a heating wire is operated to generate heat and the foam is brought into contact with the heating wire to be allowed to burst and gas in the foam is sucked by a vacuum pump 8 while a liquid is recovered to be returned to a washing tank 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for degassing dissolved gas or mixed gas from a cleaning solution containing, for example, a surfactant.

[0002]

2. Description of the Related Art Conventionally, an object to be cleaned is immersed in a cleaning liquid,
An ultrasonic cleaning device that emits ultrasonic waves into a liquid to generate minute cavitation of a vacuum nucleus and cleans an object to be cleaned with the impact force of the cavitation is known. It is known that it is effective to degas gas dissolved in the cleaning liquid or gas mixed in the cleaning liquid in order to enhance the gas diffusion property and improve the propagation characteristics. At this time, as the degassing means, a means for using a hollow fiber degassing module, or means for degassing the liquid in a vacuum vessel by shower injection or the like and degassing the gas in the liquid by evacuation is known. I have.

[0003]

However, when the cleaning liquid contains a surfactant or the like, in the hollow fiber degassing module, the inner surface of the hollow fiber becomes hydrophilic and the cleaning liquid passes as it is,
As a result, it cannot be degassed, and in the vacuum degassing method, the dissolved gas expands like a soap bubble due to the reduced pressure, and the gas becomes bubbles wrapped in a thin liquid shell, and the liquid flows to the vacuum pump side. Degassing is impossible because of the flowing in together.

On the other hand, a vacuum defoaming container for collecting bubbles is provided between the vacuum degassing container and the vacuum pump, and when a certain amount of bubbles has accumulated in the defoaming container, the inside of the vacuum container is returned to atmospheric pressure. It is also conceivable to remove bubbles and collect only the liquid, but in this method, a large amount of gas is re-dissolved in the liquid when the pressure is returned to atmospheric pressure, and a sufficient degassing effect can be obtained. Can not.

Accordingly, an object of the present invention is to effectively remove dissolved gas and mixed gas from a liquid in which bubbles are generated in a vacuum state, for example, in an ultrasonic cleaning device or the like.

[0006]

In order to achieve the above object, the present invention provides a vacuum vessel containing a heating element for removing dissolved gases and the like from a liquid in which bubbles are generated in a vacuum state,
The liquid was introduced into the vacuum container, and the bubbles were brought into contact with the heating element to break them.

That is, when the cleaning liquid is introduced into the vacuum container and degassed, the dissolved gas and the mixed gas become bubbles. The bubbles are destroyed and only the gas is discharged by the vacuum pump.
The liquid is collected and reused, for example, by circulating it.However, if bubbles are brought into contact with the heating element in the vacuum vessel and destroyed, the bubbles can be eliminated while keeping the vacuum vessel in a reduced pressure state. In addition, the amount of gas re-dissolved in the recovered liquid can be reduced.

Here, as the heating element, for example, a heating element such as a heater in which the periphery of a heating wire is covered with a resin coating or the like can be applied. If the surface temperature is heated to about 50 ° C. or more, defoaming is performed. Is quite possible.

According to a second aspect of the present invention, the vacuum container is provided with a level detecting means for detecting a bubble level and generating a heat signal to the heating element.

[0010] The generation of the heat signal by the level detecting means is more economical than the case where the heat generator is constantly heated.

According to a third aspect of the present invention, as the ultrasonic cleaning apparatus, the liquid used for cleaning in the ultrasonic cleaning tank is sent to the deaerator to remove dissolved gas and the like in the liquid and circulated again to the ultrasonic cleaning tank. I tried to make it.

As described above, it is preferable to apply the deaerator to an ultrasonic cleaning device.

[0013]

Embodiments of the present invention will be described with reference to the accompanying drawings. Here, FIG. 1 is a system configuration diagram of the ultrasonic cleaning apparatus, and FIG. 2 is a configuration diagram of the inside of the defoaming cylinder.

The ultrasonic cleaning apparatus according to the present invention is, for example, an apparatus for performing ultrasonic cleaning, ultrasonic deburring cleaning, ultrasonic polishing processing, etc., when radiating ultrasonic waves into a cleaning liquid.
In order to generate cavitation with strong impact force, gas (mainly air) dissolved or mixed in the cleaning liquid can be effectively removed, and especially water-soluble cleaning agents that easily generate bubbles in a vacuum state are used. It is effective if applied to the contained cleaning solution.

As shown in FIG. 1, the ultrasonic cleaning apparatus 1 includes an ultrasonic cleaning tank 2 for storing a cleaning liquid S containing a water-soluble cleaning agent and the like, and a lead-out line 3 connected to the ultrasonic cleaning tank 2. A deaeration cylinder 4 connected to the deaeration cylinder 4 via a connection line 5 and a vacuum pump 8 connected to the deaeration cylinder 6 via a vacuum line 7. One end of a return line 10 is connected to the degassing cylinder 4 and the defoaming cylinder 6, and the other end of the return line 10 is connected to the ultrasonic cleaning tank 2.

After the object to be cleaned is cleaned in the ultrasonic cleaning tank 2, the cleaning liquid S is sent to the degassing cylinder 4 to degas the gas contained in the liquid, and the liquid is passed through the return line 10 through the ultrasonic cleaning tank 2. 2 and the bubbles generated in the degassing cylinder 4 are sent to a defoaming cylinder 6 as a degassing device according to the present invention. The liquid is sucked and discharged by the vacuum pump 8, and the liquid is returned to the ultrasonic cleaning tank 2 through the return line 10.

The ultrasonic cleaning tank 2 includes an ultrasonic generator 11
And an overflow tank 13 juxtaposed next to the cleaning tank 12. The ultrasonic generator 11 radiates ultrasonic waves into the cleaning liquid S in the cleaning tank 12 to generate a minute vacuum. Cavitation consisting of nuclei is caused to occur, and one of the plurality of connection portions of the return line 10 is opened like a slit near the liquid surface of the cleaning liquid S to overflow the upper layer liquid of the cleaning liquid S. It can be sent to the tank 13.

A plurality of valves including a normally closed electromagnetic valve 14 are disposed in the lead-out line 3. The electromagnetic valve 14 can be opened as required to feed the cleaning liquid S to the degassing cylinder 4. ing.

The degassing cylinder 4 can be depressurized by the suction action of the vacuum pump 8 through the connection line 5. For example, the cleaning liquid S is finely divided by a filter or shower jet to increase the contact area in a vacuum atmosphere to increase the inside of the liquid. The gas contained in can be degassed.

The connection line 5 is connected in such a manner that bubbles generated in the degassing cylinder 4 can be sucked and sent to the defoaming cylinder 6, and a normally open electromagnetic valve 15 is provided in the middle thereof. Have been.

An electrode type level gauge 16 as a level detecting means as shown in FIG. 2 and a resin such as Teflon or fluorine resin are provided inside the defoaming cylinder 6 as a deaerator which is a characteristic part of the present invention. The heating wire 17 covered with the coating is accommodated, and the level gauge 16 is composed of a plurality of (three in the embodiment) detection bars having different heights. Is detected, the heating wire 17
To send electrical signals. And the heating wire 17
When an electric signal is supplied from the level gauge 16, the surface temperature is heated to about 60 to 120 ° C. The evacuation line 7 is connected to a relatively upper position of the defoaming cylinder 6, and the return line 10 is connected to a lower position.

A circulation pump 20 is provided in the middle of the return line 10, and a normally closed electromagnetic valve 2 is provided between the circulation pump 20 and the defoaming cylinder 6.
1 is disposed, and a normally open electromagnetic valve 22 is disposed between the circulation pump 20 and the deaeration cylinder 4. The vacuum line 7 is provided with an electromagnetic three-way valve.

The ultrasonic cleaning apparatus 1 configured as described above
The operation and the like of will be described. First, when the cleaning liquid S is degassed, the internal pressure of the degassing cylinder 4 and the defoaming cylinder 6 is reduced to minus 500 mmHg or less by the operation of the vacuum pump 8.

When the electromagnetic valve 14 of the outlet line 3 is opened and the cleaning liquid S in the overflow tank 13 is introduced into the degassing cylinder 4, the dissolved gas and the mixed gas (mainly air) become bubbles in the form of bubbles. It is guided to the defoaming cylinder 6 through the electromagnetic valve 15 of the connection line 5.

When the amount of the foam guided to the defoaming cylinder 6 reaches a certain amount, the level gauge 16 detects this and supplies electricity to the heating wire 17 to generate heat at about 60 to 120 ° C. Then, the bubbles in contact with the heating wire 17 burst immediately, the gas inside is sucked by the vacuum pump 8 and discharged to the outside, and the liquid which was the surface shell of the soap bubble bursts and collects below. When the liquid reaches a certain amount or more, the electromagnetic valve 21 of the return line 10 is opened and the circulating pump 20 is opened.
Is returned to the cleaning tank 12 by the operation of.

By performing the above operations continuously,
It is possible to effectively remove gas such as air contained in the cleaning agent, gas adhering to an object to be cleaned and entering into the cleaning solution S, and gas dissolving in the cleaning solution S. Can be improved.

When degassing was carried out using the defoaming cylinder 6, components of a detergent (23% of a surfactant, polyethylene ethylene alkyl ether, fatty acid alkanolamide, and sodium linear argylbenzenesulfonate) were initially obtained. ) 5%
The liquid, which contained 6 to 8 mg / l of air in 30 liters of the washing liquid S, could be reduced to 1 to 2 mg / l in 30 minutes.

The ultrasonic cleaning apparatus 1 using the defoaming cylinder 6 is used to prepare a 5% solution of the above-mentioned components at a temperature of 55 ° C.
Ultrasonic specifications 25KHz, output 1W / cm ² , 1200W
When 20 knives were buffed and removed under the conditions described above, all of them passed in 2 minutes. On the other hand, when the conventional ultrasonic cleaning apparatus was used to perform buffing removal under the same ultrasonic specifications, all of the parts failed in 5 minutes, and failed in 50 minutes in 10 minutes.
Only passed%. From these results, the effectiveness of the present invention was confirmed.

The present invention is not limited to the above embodiment. Those having substantially the same configuration as those described in the claims of the present invention and exhibiting the same operation and effect belong to the technical scope of the present invention. For example, the heating element may be a sheathed plug type heater or another solid heater, and the purpose of use of the ultrasonic cleaning device is arbitrary.

[0030]

As described above, the deaerator according to the present invention has the following features.
A vacuum vessel containing a heating element was provided, and liquid was introduced into the vacuum vessel, and the bubbles were brought into contact with the heating element to break them, so that the bubbles could be erased while keeping the inside of the vacuum vessel under reduced pressure. In addition, the amount of gas re-dissolved in the recovered liquid can be reduced. At this time, it is more economical if a level detecting means is provided in the vacuum vessel and the heating element is caused to generate heat by the detection of the level detecting means. It is preferable that such a deaerator is incorporated in an ultrasonic cleaning device.

[Brief description of the drawings]

FIG. 1 is a system configuration diagram of an ultrasonic cleaning apparatus.

FIG. 2 is a configuration diagram of the inside of a defoaming cylinder.

[Explanation of symbols]

Reference numeral 1 denotes an ultrasonic cleaning device, 6 denotes a defoaming cylinder, 16 denotes a level gauge, and 17 denotes a heating wire.

Claims (3)

[Claims] 1. A vacuum container containing a heating element is provided for removing dissolved gas or the like from a liquid in which bubbles are generated in a vacuum state, and the liquid is introduced into the vacuum container to bring the bubbles into contact with the heating element. A degassing device characterized in that it is destroyed by letting it break. 2. The degassing apparatus according to claim 1, wherein a level detecting means for detecting a level of bubbles and generating a heat signal to the heating element is provided in the vacuum vessel. Qi device. 3. The liquid used for cleaning in the ultrasonic cleaning tank is sent to the degassing device according to claim 1 to remove dissolved gases and the like in the liquid, and circulated again in the ultrasonic cleaning tank. An ultrasonic cleaning apparatus provided with a deaerator characterized by the above.