JP3379019B2 - Work cleaning device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to a work cleaning apparatus used for cleaning a work such as an electronic component and a pressed component. 2. Description of the Related Art Conventionally, as a method of cleaning a work as described above, for example, an entire work is immersed in a chlorine-based solvent stored in a cleaning tank, and an ultrasonic wave is attached to the cleaning tank. There is a cleaning method in which a vibrator is vibrated to remove foreign substances such as cutting chips and oil attached to a work by cavitation action of a chlorine-based solvent. [0003] However, when the work is cleaned only with a chlorine-based solvent as described above, the chlorine-based solvent is not only harmful to the human body and the environment, but also dissolves the resin material. It is an unsuitable solvent for cleaning resin products such as printed circuit boards because it is easy to use. And, if a small work capacity and washing treatment with chlorinated solvent, condensation occurs at the time of the work dry, since the deposited marks such as dust or dirt in the condensation portions remain, that the cleaning effect of the solvent is impaired problem Have a point. [0004] In view of the above problems, the present invention provides a residue-free cleaning process that requires an advanced technique by cleaning an uncleaned workpiece with a petroleum-based solvent and then immersing the workpiece in an FC-based solvent. It is an object of the present invention to provide a workpiece cleaning apparatus capable of easily performing the cleaning and cleaning the entire workpiece reliably and neatly. SUMMARY OF THE INVENTION [0005] A work cleaning apparatus according to the present invention is a method for cleaning an uncleaned work in a petroleum solvent heated to a temperature suitable for separating and removing foreign substances adhering to the work. A second washing tank for immersing the workpiece in an FC solvent having a higher specific gravity of the solvent itself and a lower temperature than the petroleum solvent is provided at a position subsequent to the first washing tank for performing the washing treatment by immersion in the second washing tank. The second cleaning tank is disposed downstream of the second cleaning tank.
Of solvent in which petroleum solvent and FC solvent are emulsified
Allow the flow and overflow the solvent
Is disposed and a first specific gravity separation tank for separating specific gravity is provided.
Separated by the first specific gravity separation tank into the first specific gravity separation tank
Only the petroleum solvent with a low specific gravity that floats on the liquid surface
Forming an oil discharge passage for discharging to the lower part of the first specific gravity separation tank.
On the flow side, excess FC solvent from the first specific gravity separation tank
While allowing the flow, the first specific gravity separation tank
Specific gravity for storing the FC solvent with high specific gravity separated by separation
A separation tank is provided, and the separation tank is provided downstream of the second specific gravity separation tank.
Allow overflow of FC solvent from second specific gravity separation tank
And the cleaning set above the second cleaning tank.
FC-based solvent in the steam drying area to dry processed workpieces
A solvent distillation tank for releasing steam is provided, and the second washing tank is provided.
Then, the FC solvent stored in the second specific gravity separation tank is
2 Circulating supply to the liquid surface of the washing tank and discharging,
Aggressively overflows petroleum-based solvents that have surfaced
It is a workpiece cleaning device provided with a liquid level cleaning nozzle . According to the work cleaning apparatus of the present invention , the whole work is
After being immersed in a petroleum-based solvent in a first cleaning tank heated to a temperature suitable for separating and removing foreign matter adhering to the work, foreign matter such as cutting chips and oil adhering to the work is washed and removed. The petroleum-based solvent containing foreign matter attached to the work is immersed in the FC-based solvent in the second cleaning tank having a lower temperature than the system-based solvent.
Peeling and removal are performed by a synergistic effect of a temperature difference and a specific gravity difference generated between the FC-based solvent. Compared to petroleum-based solvents with low specific gravity
The first emulsification tank separates the solvent emulsified with the heavy FC solvent.
And separate the specific gravity.
Allows light petroleum solvents to float naturally. Liquid in the first specific gravity separation tank
Only light petroleum-based solvents floating on the surface part
Drain more out of the tank. The first specific gravity is separated by the second specific gravity separation tank.
Excessive heavy FC solvent separated by heavy separation tank
Allow to flow and store. Steam set above the second washing tank
In the drying area, use the solvent distillation tank to
Heat the FC-based solvent with a high specific gravity by bar-flow
Releases solvent vapor. Further, the upper part of the second cleaning tank is
The FC solvent stored in the second specific gravity separation tank is subjected to the second washing.
Circulates and supplies to the liquid surface of the tank and discharges it, and floats on the liquid surface
Surface washing to actively overflow the oil-based solvent
A cleaning nozzle is provided to keep the FC solvent constantly exposed to the entire liquid surface of the second cleaning tank. According to the present invention, foreign matter adhering to an uncleaned work is cleaned and removed by a high-temperature petroleum solvent heated to a predetermined temperature, and then the work is removed from the petroleum solvent. Is also immersed in a low-temperature FC solvent to remove the petroleum solvent containing foreign substances adhering to the work by synergistic action between the temperature difference and the specific gravity difference generated with the FC solvent. The separation power required to remove the solvent is obtained, and the residue of petroleum-based solvents, which was difficult to remove by conventional methods, can be reliably removed by washing. Washing process without any problems can be easily performed.
Moreover, the petroleum solvent remaining on the work is peeled off and removed.
Since the entire work is finish-cleaned only with the FC solvent, the entire work can be surely and cleanly cleaned, and is optimal for cleaning precision parts such as electronic parts and electric parts. Ma
The solvent in which the petroleum-based solvent and FC-based solvent are emulsified
Separate and place light petroleum-based solvent on the liquid surface of FC-based solvent.
Floats naturally and separates it, thereby circulating the FC solvent.
Recycling is possible, and the recycling rate can be improved.
You. Furthermore, the specific gravity floating on the liquid surface of the first specific gravity separation tank
Only light petroleum solvents are discharged outside the tank through the oil drain
This facilitates the circulating supply of FC-based solvents,
Ensures that only petroleum-based solvents are
It can be discharged outside the tank. By the second specific gravity separation tank
FC solvent with high specific gravity separated in the first specific gravity separation tank
Circulates by overflowing and storing
High purity of the FC solvent can be maintained. Also
In addition, in the steam drying area set above the second washing tank,
Overflow from the second specific gravity separation tank by the solvent distillation tank
Heated FC solvent with high specific gravity
By discharging, the work taken out from the second cleaning tank
The drying treatment can be performed by heating to an appropriate temperature. and,
The petroleum solvent floating on the liquid surface of the second cleaning tank is cleaned
First specific gravity separation by FC solvent discharged from purification nozzle
Since the water overflows positively toward the tank,
The petroleum-based solvent does not stagnate on the liquid level in the
When removing the plate W from the second washing tank, the petroleum-based solvent is attached again.
Wearing can be prevented. An embodiment of the present invention will be described below in detail with reference to the drawings. The drawing shows a work cleaning apparatus used for cleaning a printed circuit board with through holes as an example of a work. In FIG.
The entire printed circuit board W is immersed in a petroleum-based solvent L (trade name: naphthesol) stored in a predetermined amount in the internal space of the cleaning chamber 2 that is hermetically sealed to wash and remove foreign substances such as cutting chips and oil. First cleaning tank 3 and FC solvent F stored in a predetermined amount
(Product name = Florinert FC-72) Printed circuit board W
Second washing tank 4 for immersing the whole to wash and remove the residual solvent
And the petroleum solvent L and FC solvent F used in the cleaning process
Separation tank 5 for specific gravity separation of FC and FC separated and recovered
A solvent distillation tank 6 for distilling the system solvent F is provided. The first cleaning tank 3 has a printed circuit board W
Petroleum solvent L (trade name =
Naphthesol) is stored in a predetermined amount, and an ultrasonic vibrator 7 for ultrasonically vibrating the petroleum solvent L is provided on the inner wall surface at the bottom of the tank. For example, the ultrasonic vibrator has a vibration frequency of 27 KHz to 200 KHz. 7 is vibrated to induce ultrasonic vibration in the petroleum solvent L. Further, a heater 8 for heating the petroleum-based solvent L is provided on the inner wall surface at the bottom of the tank, and for example, a medium such as oil or water heated to an appropriate temperature is supplied to the heater 8 by circulating the medium. The system solvent L is heated to an appropriate temperature (for example, about 60 ° C.) suitable for separating and removing foreign matter such as cutting chips and oil attached to the printed circuit board W. In addition, one end of a liquid circulation path 13 is connected to the lower liquid storage area of the first washing tank 3 via a valve 9, a circulation pump 10, a filter 11, and a heat exchanger 12, and the same. The other end of the liquid circulation path 13 is connected to the first
It is connected to the upper storage area of the washing tank 3. That is, the circulating pump 10 is driven to circulate and supply the petroleum solvent L stored in the first cleaning tank 3 via the filter 11 and the heat exchanger 12. The above-described tanks 4, 5, and 6 are arranged sequentially on the bottom of a finishing chamber 15 formed inside the same chamber, and are positioned immediately above the second cleaning tank 4. Printed circuit board W
Forms a work entrance 16 of a size that allows entry and exit,
A cooling jacket 17 is provided along the lower side wall surface of the work entrance 16 corresponding to the upper steam region of the second cleaning tank 4, and the upper steam of the water separation tank 19 connected to the lower side wall surface of the work entrance 16 is provided. A cooling coil 18 is disposed in the region, and for example, a refrigerant cooled to an appropriate temperature is circulated and supplied to the cooling jacket 17 and the cooling coil 18, and the FC solvent F discharged into the upper steam region of the second washing tank 4 is discharged. The temperature of the cooling jacket 17 and the cooling coil 18 is maintained at a temperature at which the vapor Fa and the moisture in the air entering the room condense and liquefy. The above-mentioned second cleaning tank 4 contains a printed circuit board W
A predetermined amount of FC solvent F (trade name: Florinert FC-72), which has a higher specific gravity of the solvent itself than the petroleum solvent L described above and is kept at a low temperature, is stored at the storage level where the whole is immersed, An ultrasonic vibrator 20 for ultrasonically vibrating the FC-based solvent F is provided on the inner wall surface of the bottom of the tank.
The ultrasonic vibrator 20 is vibrated at a vibration frequency of 200 KHz to induce ultrasonic vibration in the FC solvent F. In addition, a liquid level cleaning nozzle 21 is disposed on the upstream side wall surface at a height level that is horizontal with respect to the petroleum solvent L floating on the liquid level portion of the second cleaning tank 4. The discharge direction is fixed toward the specific gravity separation tank 5 disposed downstream. In addition, between the upper end wall of the second washing tank 4 arranged on the upstream side and the specific gravity separation tank 5 arranged on the downstream side, the specific gravity separation tank on the downstream side from the second washing tank 4 on the upstream side. 5 for overflowing each of the solvents L and F emulsified toward 5
2 is oblique. In the specific gravity separation tank 5, a partition plate 5c is provided upright at a position where the liquid storage area inside the tank is divided into a first separation tank 5a and a second separation tank 5b. A partition plate 5d is provided upright at a position where the liquid storage region 5b is divided into right and left. An oil drainage path 24 is connected via a valve 23 to the oil floating area of the petroleum solvent L floating on the liquid surface of the first separation tank 5a, and is connected to the lower liquid storage area of the second separation tank 5b. One end of the liquid circulation path 29 is connected via a valve 25, a circulation pump 26, a filter 27, and a heat exchanger 28, and the other end of the liquid circulation path 29 is connected to each of valves 30 and 31.
Are connected to the upper liquid storage area of the second cleaning tank 4 and the liquid level cleaning nozzle 21 via the second cleaning tank 4. That is, the circulation pump 26
To drive the FC solvent F stored in the second separation tank 5b of the specific gravity separation tank 5 via the filter 27 and the heat exchanger 28 into the upper storage area of the second cleaning tank 4 and the liquid level cleaning nozzle. 21
And circulate supply. The solvent distillation tank 6 is provided with a heater 32 for heating the FC solvent F on the inner wall surface at the bottom of the tank, for example, a medium such as oil or water heated to an appropriate temperature. Is circulated and supplied to the heater 32 to heat the FC solvent F to a boiling point at which the FC solvent F evaporates (for example, about 56 ° C.). and,
Between the upper end walls of the specific gravity separation tank 5 disposed on the upstream side and the solvent distillation tank 6 disposed on the downstream side, the specific gravity is separated from the specific gravity separation tank 5 on the upstream side toward the solvent distillation tank 6 on the downstream side. The falling plate 33 for overflowing the FC solvent F is inclined. Assuming that the illustrated embodiment is configured as described above, a method of cleaning the printed circuit board W by the work cleaning apparatus 1 will be described below. First, as shown in FIG. 1, a heater 8 disposed in the first cleaning tank 3 is heated to separate and remove the petroleum-based solvent L stored in the tank from foreign matters adhering to the printed circuit board W. Suitable temperature (eg, about 60
(° C). Thereafter, the uncleaned printed circuit board W is carried into the cleaning chamber 2, and the entire printed circuit board W is immersed in the petroleum-based solvent L stored in the first cleaning tank 3, and then disposed at the bottom of the tank. Since the ultrasonic vibrator 7 is vibrated to wash and remove the printed circuit board W by the cavitation action of the petroleum-based solvent L, foreign substances such as chips and oil adhering to the printed-circuit board W can be reliably removed by the cleaning power of the petroleum-based solvent L. Can be washed away. At the same time, the circulating pump 10 is driven to circulate and supply the petroleum-based solvent L stored in the first washing tank 3 via the filter 11 and the heat exchanger 12. Next, the heater 32 disposed in the solvent distillation tank 6 is heated to heat the FC solvent F stored in the tank to an appropriate temperature (for example, about 56 ° C.) and to evaporate. The vapor Fa of the vaporized FC solvent F is discharged to the entire finishing chamber 15. Thereafter, the printed circuit board W subjected to the primary cleaning is carried into the finishing chamber 15, passed through the vapor Fa of the FC solvent F discharged into the upper vapor region of the second cleaning tank 4, and stored in the tank. After being immersed from above in the FC solvent F, which has a higher specific gravity than the liquid petroleum solvent L and has a lower temperature,
By vibrating the ultrasonic transducer 20 disposed at the bottom of the tank, F
The petroleum-based solvent L containing foreign matter adhered to the printed circuit board W is removed by cavitation of the C-based solvent F. That is, since the FC solvent F has a lower surface tension and is superior in permeability as compared with chlorofluorocarbon and the like, the petroleum solvent L attached to the surface portion of the printed circuit board W can be reliably peeled and removed. . At the same time, the high-temperature petroleum solvent L peeled and removed from the printed circuit board W is emulsified in the FC solvent F, and the high-temperature, light-weight petroleum solvent L is spontaneously floated on the liquid surface of the second cleaning tank 4. Let it. The circulating pump 26 is driven to remove the FC solvent F stored in the second separation tank 5 b of the specific gravity separation tank 5 via the filter 27 and the heat exchanger 28 into the liquid in the second washing tank 4. The liquid is supplied to the surface cleaning nozzle 21 in a circulating manner.
The petroleum-based solvent L containing foreign matters floating on the liquid surface of the second washing tank 4 is removed from the FC-based solvent F discharged from the tank 1 by a specific gravity separation tank 5.
Is positively overflowed toward the first separation tank 5a, and the state in which the FC solvent F is always exposed to the entire liquid surface of the second washing tank 4 is maintained. Next, the respective solvents L and F having different specific gravities overflow to the first separation tank 5a side of the specific gravity separation tank 5 in a state of being emulsified, and the FC solvent F having a high specific gravity and the petroleum system having a light specific gravity are overflowed. Separation from solvent L by specific gravity. That is, the petroleum-based solvent L having a low specific gravity naturally floats on the liquid surface of the FC solvent F stored in the first separation tank 5a of the specific gravity separation tank 5, and floats on the liquid surface of the first separation tank 5a. Only the petroleum-based solvent L having a low specific gravity is discharged from the oil discharge passage 24 to the outside of the tank. On the other hand, the heavy FC-based solvent F stored in the lower storage area of the first separation tank 5a overflows to the second separation tank 5b side,
The FC solvent F stored in the separation tank 5b overflows to the solvent distillation tank 6 side. At the same time, the FC solvent F stored in the solvent distillation tank 6 is heated by the heater 32 to release the vapor Fa of the FC solvent F to the entire finishing chamber 15 and to remove the vapor Fa from the second cleaning tank 4. The cooling jacket 17 disposed in the upper steam area
Since the vapor Fa of the C-based solvent F is condensed and liquefied, the distilled FC-based solvent F is supplied dropwise to the second cleaning tank 4. Next, after the cleaning is completed, the entire printed circuit board W is taken out from the FC solvent F stored in the second cleaning tank 4, and the FC solvent F discharged into the upper vapor region of the tank is removed.
The entire printed circuit board W is heated to an appropriate temperature with the steam Fa and dried. Thereafter, the cleaned printed circuit board W is unloaded from the finishing chamber 15 and the printed circuit board W is unloaded from the cleaning chamber 2 to complete the cleaning process for one printed circuit board W. As described above, after the foreign matter adhering to the uncleaned printed circuit board W is removed by washing with the high temperature petroleum solvent L heated to a predetermined temperature, the printed circuit board W is removed more than the petroleum solvent L. The specific gravity of the solvent itself is immersed in the FC solvent F having a large specific gravity and a low temperature, and the petroleum solvent L containing the foreign matter adhering to the printed circuit board W is separated from the temperature difference and the specific gravity difference generated between the solvent L and the FC solvent F. Since separation and removal are performed by synergistic action, a large separation force required for separating the petroleum-based solvent L is obtained,
Petroleum-based solvent L, which was difficult to remove by conventional methods
Residue can be reliably removed by washing, and a residue-free washing process requiring advanced technology can be easily performed. Moreover, since the petroleum-based solvent L remaining on the printed circuit board W is peeled off and the printed circuit board W is finished and cleaned only with the FC-based solvent F, the entire printed circuit board W can be reliably and cleanly cleaned, and electronic components and the like can be cleaned. Ideal for cleaning precision parts such as electrical parts. In addition, petroleum solvents and FC solvents
The emulsified solvent is separated by specific gravity and applied to the liquid surface of the FC solvent.
Separating natural petroleum solvents with low specific gravity by floating naturally
This makes it possible to circulate and supply FC solvents and improve the recycling rate.
You can aim up. Further, the liquid level of the first specific gravity separation tank
Only the petroleum solvent with a low specific gravity that floats on the part
Discharge to the outside of the tank so that the FC solvent can be circulated and supplied.
Simplicity and without the need for complex oil drains
Only the petroleum solvent can be discharged outside the tank. No.
Specific gravity separated in the first specific gravity separation tank by 2 specific gravity separation tank
To overflow and store heavy FC solvent
The purity of the circulating FC solvent should be kept high.
Can be. In addition, it was set above the second washing tank.
In the steam drying area, from the second specific gravity separation tank by the solvent distillation tank
The overflowed heavy FC solvent is heated to F
By releasing the vapor of the C-based solvent, it is removed from the second cleaning tank.
Heating the delivered work to an appropriate temperature for drying
Can be. Further, the petroleum-based solvent L floating on the liquid surface portion of the second cleaning tank 4 is positively overflowed toward the specific gravity separation tank 5 by the FC-based solvent F discharged from the injection nozzle 21, so that the second cleaning is performed. The petroleum-based solvent L does not stagnate on the liquid surface portion of the tank 4, and it is possible to prevent the petroleum-based solvent L from adhering again when the printed circuit board W is taken out from the second cleaning tank 4. In correspondence between the configuration of the present invention and the above-described embodiment, the work of the present invention corresponds to the printed circuit board W of the embodiment, but the present invention is limited to only the configuration of the above-described embodiment. Not something. In the above embodiment, the printed circuit board W is cleaned with the FC solvent F (trade name: Fluorinert FC-72). For example, FC-40, FC-43, and FC-7 are used.
FC solvent F such as 0, FC-75, FC-77, and FC-104 may be selected and used according to the intended use.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall configuration diagram showing a cleaning method using a work cleaning apparatus. [Description of Signs] W ... Printed circuit board L ... Petroleum solvent F ... FC solvent 1 ... Work cleaning device 3 ... First cleaning tank 4 ... Second cleaning tank 5 ... Specific gravity separation tank 6 ... Solvent distillation tanks 7, 20 ... Ultrasonic transducer

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) B08B 1/00-7/04

Claims (1)

(57) [Claims] [Claim 1] A cleaning process in which an uncleaned work is immersed in a petroleum-based solvent heated to a temperature suitable for separating and removing foreign matters adhering to the work. In the position after the first washing tank
A second cleaning tank for immersing the workpiece in an FC solvent having a higher specific gravity of the solvent itself than the petroleum solvent itself and having a lower temperature is disposed , and the second cleaning tank is provided downstream of the second cleaning tank. From 2 washing tanks to petroleum
Solvent overflow of solvent emulsified with FC solvent
Allow and store the overflowed solvent.
A first specific gravity separation tank for performing specific gravity separation is provided, and the first specific gravity separation tank is separated into the first specific gravity separation tank by the first specific gravity separation tank.
Only petroleum-based solvents with a low specific gravity that have separated and floated on the liquid surface
An oil discharge passage for discharging the oil to the outside of the tank, and the first specific gravity separation tank is provided downstream of the first specific gravity separation tank.
Allow the FC solvent to overflow,
FC system with heavy specific gravity separated by the first specific gravity separation tank
A second specific gravity separation tank for storing a solvent is provided, and the second specific gravity separation tank is provided downstream of the second specific gravity separation tank.
While allowing the overflow of these FC solvents,
Dry the cleaned work set above the second cleaning tank
Solvent that releases vapor of FC solvent into the steam drying area to be treated
A FC distillation tank is disposed in the second washing tank and the FC stored in the second specific gravity separation tank.
The system solvent is circulated and supplied to the liquid surface of the second cleaning tank and discharged.
And the oil-based solvent floating on the liquid surface
-A workpiece cleaning device equipped with a liquid level cleaning nozzle for flow .