JPH06101080A - Work cleaning method and cleaning device - Google Patents

Abstract

(57) [Summary] [Object] The present invention realizes extremely high cleanliness in a water washing process without causing stains and detergent residue even on a work having a complicated shape. The present invention is characterized in that in a water washing process, preliminary washing with a rust preventive aqueous solution, washing and rinsing under a reduced pressure atmosphere are performed, and a water reclaiming apparatus and a deaeration apparatus are provided in a rinsing step.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for cleaning a work, and more particularly to a technology for cleaning a metal part having a complicated shape.

[0002]

2. Description of the Related Art A halogenated hydrocarbon type cleaning agent typified by trichloroethane has a high cleaning ability for a work, and since the cleaning agent can be directly dried and removed from the cleaned work, it is suitable for cleaning the work. Since it has no reactivity with metals, it is widely used for cleaning works such as circuit boards and metal parts. However, since the halogenated hydrocarbon-based cleaning agent has a problem for the human body and a problem of environmental destruction, it is being replaced with a cleaning solution containing a surfactant and the like. In the cleaning method using the cleaning liquid containing the surfactant, for example, there is a process as shown in FIG. Here, the apparatus 1 is a cleaning unit, 201 is a cleaning liquid, 202 is an ultrasonic vibrator, and 203 is a pump for circulating the cleaning liquid. Next, the device 2 is a preliminary rinse part, 204 is a rinse liquid containing an anticorrosive agent, and 205 is a circulation pump. The device 3 is a rinsing unit and employs a two-stage rinsing system. Reference numeral 206 denotes an ultrasonic vibrator, which is used as the first rinse and performs the final rinse with the second rinse.
Finally, the apparatus 4 is a drying section, 207 is a main body, and 208 is a heat-generating heater. In the case of performing water cleaning as is clear in the cleaning process of FIG. 2, the cleaning agent adhering to the work after cleaning cannot be removed from the work only by drying. Therefore, the work is rinsed with water and removed. To do. Then, the water adhering to the work is further removed by drying.

[0003]

However, since a detergent containing such a surfactant is inferior in cleaning ability and permeation ability as compared with trichloroethane, a component having a non-penetrated hole or a fine penetrating hole cannot be obtained. However, there is a problem in that insufficient cleaning is likely to occur, and when a large amount of dirt is introduced into the cleaning liquid, the cleaning property is sharply reduced. Further, such a part having a non-through hole or a thin through hole has a problem that it is difficult to obtain a clean surface after cleaning because it is difficult to remove the attached work cleaning agent.

Therefore, a method of improving the cleaning property and the rinsing property by strengthening the physical force of ultrasonic cleaning or shower cleaning can be considered. However, if this method is adopted, the damage to the work becomes large, so it cannot be a practical countermeasure.

In view of the above problems, an object of the present invention is to carry out preliminary cleaning, cleaning and rinsing under reduced pressure, addition of a water-soluble organic solvent to rinsing water, and installation of a water regeneration treatment device and a deaerator. Accordingly, it is an object of the present invention to provide a work cleaning method having a high cleaning property for a component having a complicated shape and a cleaning device for performing the method.

[0006]

In order to solve the above-mentioned problems, the present invention provides a method of cleaning with water or suction in a pre-cleaning step in order to prevent dirt adhering to a work from being brought into a cleaning solution. It is characterized by removing dirt. Here, the pre-cleaning does not use a cleaning agent, and since air is used as a medium when removing by suction, dirt can be easily separated and collected. Further, the cleaning step is characterized in that the dirt attached to the details of the work such as a non-through hole is extruded, and the pressure is reduced in the atmosphere and the cleaning solution in order to allow the cleaning solution to penetrate into the details. In the rinsing process, depressurize in water to remove the cleaning agent adhering to the work, and a regeneration treatment device by a filtration method using activated carbon to keep the rinse water at a high cleanliness level, and degassing. It is characterized in that it is equipped with a device and that a water-soluble organic solvent is added and impregnated in the rinse liquid and the activated carbon.

The organic solvent used here is characterized by having a carbon number of 3 or less and a lower molecular weight than the cleaning agent in the cleaning liquid.

[0008]

【Example】

(Embodiments 1 to 16) Next, a cleaning apparatus according to Embodiments 1 to 16 of the present invention will be described with reference to FIG.

FIG. 1 schematically shows the overall construction of the work cleaning apparatus of this example. The apparatus of this example is for cleaning metal parts (work), and is configured to collectively clean the work using a cleaning basket. As shown in FIG. 1, the apparatus 1 according to the present embodiment includes a preliminary cleaning unit 2, a reduced pressure cleaning unit 3, a cleaning unit 4, a preliminary rinse unit 5, a reduced pressure rinse unit 6, and a final rinse in order from the upstream side of the work transfer path. It has a configuration in which the section 7 and the drying section 8 are arranged.

Next, the structure of each part will be described with reference to FIG.

First, in the preliminary cleaning section 2, the cleaning tank 1 in which water 101 containing a rust preventive agent for the work is stored.
From 02, the work is pre-cleaned by spraying the work in the air. Here, the cleaning tank 102 has a substantially cubic shape with the upper part opened, and the inner walls of the four-sided walls are
Six full-cone type nozzles 103 having an injection angle of 60 degrees are arranged. These nozzles 103 inject the water containing the rust preventive agent for the work from a diagonally upper position with respect to the cleaning basket 104 conveyed into the cleaning tank 102. Further, these nozzle groups are connected to the cleaning tank 102 via the water circulation path 105.
A pump 106 and an oil / water separator 107 are inserted in the circulation path 105.

Next, in the reduced pressure cleaning unit 3, the pre-cleaned work is immersed in the cleaning liquid tank 109 in which the water-based cleaning agent 108 is stored, the cleaning liquid tank 109 is closed by a shutter 110, and the rotary pump 111 and The pressure is reduced by the mechanical booster pump 112. These vacuum pumps (rotary pump 111, mechanical booster pump 112) are provided with a suction port 113 at the upper part of the cleaning liquid tank 109, the degree of vacuum is adjusted by a leak valve 114, and the air above the cleaning liquid tank is discharged from an exhaust port 115. Exhaust.

Next, in the cleaning section 4, the pre-cleaned work is cleaned by a cleaning liquid tank 11 in which an aqueous cleaning agent 116 is stored.
It is immersed in No. 7 and ultrasonically cleaned. Here, the cleaning liquid tank 117 also has a substantially cubic shape with the upper part open, and for the cleaning liquid 116 stored in the cleaning liquid tank 117, the ultrasonic oscillator 118 arranged on the bottom side of the cleaning liquid tank 117.
Thus, an ultrasonic wave having a frequency of 28 kHz can be propagated.

Next, in the preliminary rinse section 5, the work is immersed in a rinse liquid tank 120 in which a rinse liquid 119 mixed with a rust preventive agent having a rust preventive action is stored. Rinse 1
The cleaning liquid adhering to the work is washed off by rocking the work up and down in the state of being immersed in 19.

Next, in the depressurized rinse section 6, the work is carried into the rinse liquid tank 120 which stores the rinse liquid 121 mixed with the rust preventive agent having the rust preventive action, and the rinse liquid 12 is supplied.
In the state where the work is dipped in 1, the rinse liquid tank 122 is closed by the shutter 123, and the rotary pump 12
4 and a mechanical booster pump 125 to reduce the pressure. These vacuum pumps (rotary pump 124, mechanical booster pump 125) are used for the rinse liquid tank 12
2 is provided with a suction port 126 on the upper part of the leak valve 1
The degree of vacuum is adjusted by 27, and the air above the rinse liquid tank is exhausted through the exhaust port 128.

Next, in the final rinse section 7, pure water 1
Ultrasonic cleaning is performed inside the pure water tank 130 in which 29 is stored to wash off the cleaning liquid from the work. Pure water tank 1
30 has a substantially cubic shape with the upper part open, and the pure water 12 is supplied by the ultrasonic generator 131 arranged on the bottom side.
An ultrasonic wave having a frequency of 28 kHz can be propagated to the antenna 9. On the bottom surface side of the pure water tank 130, a circulation path 132 for drawing pure water out of the tank and returning it to the pure water tank 130 is arranged.
3, a pure water regeneration unit 134, and a steam separation unit 135 (deaerator) are inserted.

Here, the pure water regenerating unit 134 is provided with an activated carbon filtration section 134a, a cation ion exchange section 134b and an anion ion exchange section 134c, removes impurities from the circulating pure water and regenerates the pure water for use. It is supposed to do.

Finally, in the drying section 8, the work is carried in and installed on the suction port 136, and the turbo fan 137 drains the work by suction force. Further, the work is exposed to a high temperature atmosphere to remove water adhering to the work. Here, the upper surface cover 139 of the drying chamber 138 can be opened and closed according to the timing of loading and unloading the work.

Next, in the work cleaning apparatus 1 having this structure, the work 30 having a deep non-through hole as shown in FIG.
1. Wash 1 The cleaning method is as follows.

1000 pieces of the work to which the cutting oil is attached are put into a cleaning basket 104 having a diameter of 15 cm and a height of 15 cm, and first, in the preliminary cleaning section 2, water 101 from the nozzle 103 is placed.
The air shower was performed at room temperature to remove the cutting oil adhering to the surface to some extent. The injection pressure at this time is 1 kg / s
q. cm.

With respect to the oil separated from the work, the floating oil is separated and collected by the oil / water separator 107, and only the water returns to the cleaning tank 103 from the circulation path 105.

Next, in the vacuum cleaning unit 3, the work 30 is
1 cleaning basket 104 containing nonionic surfactant cleaning liquid 1
The cleaning liquid tank 109 is sealed by immersing it in 08 and closing the shutter 110.
Was operated and the pressure was gradually reduced to 20 torr. The cleaning liquid 108 at this time was 22 degrees or less. Vacuum degree is 20
After reaching torr, the vacuum degree was maintained for 1 minute by opening and closing the leak valve 114. At this time, the gas existing in the unpenetrated hole expands and pushes the adhered oil out of the hole.

After that, the leak valve 114 was opened to return the inside of the cleaning liquid tank to the normal pressure. At this time, the gas existing in the unpenetrated hole is compressed and the cleaning liquid is taken into the hole.

Next, in the cleaning unit 4, ultrasonic cleaning was performed for 10 minutes. The dirt on the surface of the work is completely cleaned, and the dirt attached to the inner wall of the unpenetrated hole is emulsified in the cleaning liquid. Next, in the preliminary rinse section 5, the work is vertically swung in the rinse liquid 120 at room temperature, and the cleaning liquid attached to the work is washed off.

Next, in the decompression rinse section 6, the work 3
The cleaning basket 104 containing 01 was immersed in the rinse liquid 121, the shutter 126 was closed to close the rinse liquid tank 122, and the rotary pump 124 was operated to gradually reduce the pressure to 20 torr. At this time, the rinse liquid 121 was set to 22 degrees or less. The degree of vacuum is 20 torr
Then, the leak degree was maintained for 1 minute by opening and closing the leak valve 127. At this time, the gas existing in the unpenetrated hole expands, and the cleaning agent emulsified by the adhered oil is pushed out of the hole. After that, the leak valve 127 is released to return the inside of the rinse liquid tank to the normal pressure. At this time, the gas existing in the non-through hole is compressed and the rinse liquid is taken into the hole.

Next, the final rinse section 7 was rinsed with pure water for 10 minutes. The cleaning liquid and water attached to the work are completely replaced with the rinse liquid 129. Here, the pure water has a dissolved oxygen amount of about 0.5 ppm due to the deaerator 135.
Since the amount is reduced below, the work does not react with the pure water and the dissolved oxygen in the pure water during the rinsing, and the work does not rust.

If water containing at least one selected from the group consisting of methanol, ethanol, isopropyl alcohol, n-propyl alcohol and acetone is used in this rinse solution, the rinse property is remarkably improved. Furthermore, since these organic solvents are nonionic and have low adsorptivity for activated carbon, they can be recycled and used. The organic solvent may be added directly to water or may be impregnated with activated carbon.

Finally, in the drying section 8, a cleaning basket was installed at the suction port 136, and the water attached to the work was sucked by the turbo fan 137. Since suction is performed from below the cleaning basket, there is little collision between works and scratches and dents are less likely to occur. Also, since it has good draining properties, it is less likely to cause stains. Further, the shutter 139 was closed, and the inside of the dryer 138 was maintained in a high temperature atmosphere for drying.

Since the cleaning and rinsing are performed under reduced pressure, the cleaning liquid or water spreads to every corner of the work, and no cleaning residue remains on the dried work.

Tables 1 and 2 show various conditions of the reduced pressure cleaning, the reduced pressure rinse, the preliminary cleaning and the final rinse of Examples 1 to 16. In addition, preliminary cleaning, main cleaning, preliminary rinse, final rinse,
Each drying step is 10 minutes.

[0031]

[Table 1]

[0032]

[Table 2]

(Examples 17 to 24) By carrying out the reduced pressure washing step in Examples 1 to 16 as follows, the washing property is further improved.

In the depressurized cleaning section, the cleaning basket containing the work is conveyed to the cleaning tank, and the shutter is closed by closing the shutter without being immersed in the cleaning liquid, and the rotary pump is operated to reduce the pressure to 20 torr. At this time, the gas existing in the uncompleted holes expands and pushes the adhered dirt out of the holes, and at the same time, many bubbles exist in the holes due to foaming during depressurization.

Then, the leak valve is opened to return the inside of the cleaning liquid tank to normal pressure.

Next, the cleaning basket 10 containing the work 301.
4 is immersed in the cleaning liquid 108, and the shutter 110 is closed to close the cleaning liquid tank 109, operate the rotary pump 111, and gradually reduce the pressure to 20 torr. The cleaning liquid 108 at this time is 22 degrees or less. When the degree of vacuum reaches 20 torr, the degree of vacuum is maintained for 30 seconds by opening and closing the leak valve 114. At this time, the gas existing in the unpenetrated hole expands and pushes the adhered oil out of the hole.

After that, the leak valve 114 is opened to return the inside of the cleaning liquid tank to the normal pressure. At this time, the gas existing in the unpenetrated hole is compressed and the cleaning liquid is taken into the hole.

As described above, since the pressure is first reduced in the atmosphere, air bubbles easily enter the holes and dirt is easily pushed out.

Therefore, it is possible to obtain a sufficient cleaning quality even for a work having a large amount of dirt in the uncompleted holes.

Table 3 shows various conditions of vacuum cleaning, vacuum rinsing and preliminary cleaning in Examples 17 to 24. The holding time at the vacuum degree of 20 torr or less in the reduced pressure cleaning section and the reduced pressure rinse section was 30 seconds, and the other steps were 10 minutes.

[0041]

[Table 3]

(Embodiments 25 to 32) The cleaning devices according to Embodiments 25 to 32 will be described.

The pre-cleaning section in FIG. 1 was changed to that shown in FIG. 4, and the subsequent steps were the same as in Examples 1-8.

The cleaning basket containing the work was conveyed to a vacuum suction port having a taper, allowed to stand still, and sucked by a suction device connected by a pipe to remove dirt adhering to the surface of the work by suction. Table 4 shows various conditions in that case.

[0045]

[Table 4]

As a comparative example, Table 5 shows conditions when the conventional work cleaning apparatus 1 as shown in FIG. 1 is used.

[0047]

[Table 5]

The results of washing under the conditions shown in Tables 1 to 5 are shown in Tables 6 and 7. The amount of oil residue is CFC-1
The adhering oil was extracted with No. 13 and calculated from the peak height due to the hydrocarbon group near 2880 / cm.

[0049]

[Table 6]

[0050]

[Table 7]

As is clear from the above results, Examples 1 to 1
No. 32 has a significantly smaller amount of residual oil than Comparative Examples 1 to 4, that is, the cleaning property is remarkably good.

[0052]

As is apparent from the above examples and comparative examples, the present invention makes it possible to clean a part having a non-through hole or a thin through hole with a good cleaning degree.

It can be said that the present invention becomes an extremely important means in the aqueous cleaning method.

[Brief description of drawings]

FIG. 1 is a diagram showing an overall configuration of a cleaning apparatus of the present invention.

FIG. 2 is a diagram showing an overall configuration of an example of a conventional cleaning device.

FIG. 3 is a view showing a work shape having a deep unpenetrated hole which is an example of a work that is difficult to clean.

FIG. 4 uses air as a medium in the preliminary cleaning unit of the present invention,
The figure which shows the suction device which removes the work adhesion oil.

[Explanation of symbols]

101 water containing rust preventive agent in the preliminary cleaning section 102 〃 cleaning tank 103 〃 nozzle for spraying water containing rust preventive agent 104 cleaning basket 105 circulating pipe communicating with the nozzle in the preliminary cleaning section 106 pump 107 in the preliminary cleaning section Oil / water separator 108 Decompression 〃 Water-based cleaning solution 109 〃 Cleaning solution tank 110 〃 Shutter 111 Rotary pump 112 Mechanical booster pump 113 Suction port in decompression cleaning section 114 〃 Soak valve 115 〃 Exhaust port 116 Ultrasonic cleaning solution 117 〃 Super cleaning tank Oscillator 119 Rinse water containing rust preventive agent in preliminary rinse section 120 〃 Rinse liquid tank 121 Rinse water containing rust preventive agent in depressurized rinse section 122 〃 Rinse solution tank 123 〃 Shutter 124 Rotary pump 125 Mechanical booster pump 126 Suction port in decompression rinsing part 127 〃 Soak valve 128 〃 Exhaust port 129 Pure water for rinsing in final rinsing part 130 〃 Rinsing tank 131 〃 Ultrasonic generator 132 〃 Circulation pipe 133 Pump 134 Pure water regeneration unit 135 Gas water Separation unit 136 Work cleaning basket suction port in drying section 137〃Suction turbofan 138〃Drying chamber 139〃 top cover 201 Cleaning part cleaning liquid in conventional cleaning process 202 Ultrasonic transducer 203 Pump 204 Rust preventive agent in preliminary rinse part Rinse water 205 Pump 206 Ultrasonic transducer 207 Drying unit main body 208 Exothermic heater 301 Workpiece with unpenetrated hole 401 Workpiece cleaning basket suction port of suction device in the preliminary cleaning unit of the present invention 402 〃 Turbo for suction § down

Claims (15)

[Claims] 1. A cleaning step for washing off adhered substances and the like from a work using a cleaning liquid, a rinse step for washing off the cleaning liquid adhering to the work using water containing an anticorrosive agent for the work, and a adhesion process for the workpiece. A method and a device for cleaning a work, comprising a drying step of drying and removing the water being processed. 2. The work cleaning method and the cleaning apparatus according to claim 1, further comprising a preliminary cleaning step of cleaning adherents from the work prior to the cleaning step. 3. The work cleaning method according to claim 2, wherein the preliminary cleaning step uses water containing a rust preventive agent for the work. 4. The work cleaning method according to claim 2, wherein in the preliminary cleaning step, an adhering substance is suctioned and removed from the work by using suction force. 5. The method for cleaning a work according to claim 1, wherein the cleaning step includes a cleaning step including at least one of a cleaning method for decompressing a work in air and a cleaning method for decompressing a work in a cleaning liquid or water. And cleaning equipment. 6. The work cleaning method according to claim 1, further comprising a step of depressurizing the work in water prior to the rinsing step. 7. The work cleaning apparatus according to claim 1, wherein the rinsing step includes a circulation means for circulating water and a regeneration means for removing impurities contained in the circulating water. 8. The water regenerating unit according to claim 7,
A work cleaning device comprising a filtering means for filtering water to separate impurities. 9. The work cleaning device according to claim 8, wherein the filtering means utilizes an adsorption effect of activated carbon. 10. The method for cleaning a work according to claim 7, wherein a water-soluble organic solvent having a low molecular weight is dissolved in water to be circulated. 11. The method for cleaning a work according to claim 10, wherein the organic solvent is an alcohol having 3 or less carbon atoms. 12. The organic solvent according to claim 11, wherein the organic solvent is
A method for cleaning a work, which is an organic solvent having a molecular weight smaller than that of the cleaning liquid according to claim 1. 13. The method for cleaning a work according to claim 9, wherein the activated carbon is impregnated with a water-soluble organic solvent. 14. The method for cleaning a work according to claim 13, wherein the organic solvent is an alcohol having 3 or less carbon atoms. 15. The organic solvent according to claim 13,
A method for cleaning a work, which is an organic solvent having a molecular weight smaller than that of the cleaning liquid according to claim 1.