JP2004016919A - Washing apparatus for work having fine pores and washing method of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a washing technique capable of efficiently removing burr, foreign matter or the like adhering to the insides of the fine pores of a work having fine pores like a ferrule. <P>SOLUTION: An ultrasonic vibrator 4 oscillating a frequency of 1 to 5 MHz and a washing liquid E possible to degass are housed in a washing tank 1 and a work holding fixture 3 is arranged above the ultrasonic vibrator 4. A work holding hole 3h and an almost conical guide hole 3g with a taper angle (θ) of 60° or more are provided to the work holding fixture 3 at the place corresponding to the region just above the ultrasonic vibrator 4 so as to pierce the same up and down and, after the work W having fine pores b is inserted in the holding hole 3h to be positioned, the amount of dissolved oxygen of the washing liquid E is set to 3 mg/l or less and the jet stream of the washing liquid E is blown up toward the work W by operating the ultraviolet vibrator 4. This jet stream is passed through the fine pores b of the work W through the guide hole 3g to wash the inside of the fine pores b. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a technique for cleaning a work having micro holes such as a ferrule used when connecting an optical fiber to a connector.
[0002]
[Prior art]
Conventionally, for example, ferrules used for connection of optical fiber connectors, for example, are generally manufactured from, for example, zirconia ceramics or the like. In recent years, metal ferrules have also been manufactured. Such a ferrule is provided with a fine hole for setting the center of the core of the optical fiber at the center of the connector. If burrs or foreign substances are left in the fine hole, the center of the core of the optical fiber will be lost. For example, after manufacturing, the optical fiber may be manually passed through the fine holes to clean the inside, or may be immersed in a cleaning solution of an ultrasonic cleaning device for cleaning, for example, after manufacturing, since the connection may be shifted or a connection loss may occur. I am trying to do it.
On the other hand, as a technique for cleaning the inside of a fine hole by ultrasonic cleaning, for example, a technique as disclosed in Japanese Patent Application Laid-Open No. Hei 7-3480 is known. In this technique, a work having a large number of fine holes is held by an arm, The holes are oriented vertically, a part of the lower end is immersed in the cleaning liquid, and a KHz-class ultrasonic oscillator is operated in the cleaning liquid below the workpiece, so that the jet of the cleaning liquid passes through the fine holes. I try to wash it.
[0003]
[Problems to be solved by the invention]
However, the method of manually cleaning the manufactured ferrules one by one through an optical fiber one by one as in the former method is time-consuming and time-consuming to perform the entire process, and the latter method is not practical. The method in which the work is simply immersed in the cleaning tank and cleaned using an ultrasonic cleaning device as in the above method cannot effectively clean the inside of the hole. The technique of holding a work with an arm, such as No. 3480, is not suitable for a small work such as a ferrule, and the strength of the jet flow is limited in a KHz-class ultrasonic oscillator. There is a problem that the cleaning effect is reduced when the cleaning is performed by positioning the cleaning member in the position.
[0004]
Accordingly, an object of the present invention is to provide a cleaning technique capable of effectively removing burrs and foreign substances adhered to the inside of a fine hole in a small work such as a ferrule and a work having a fine hole. .
[0005]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a cleaning apparatus for cleaning a workpiece having fine holes, a cleaning tank containing an ultrasonic oscillator and a cleaning liquid, and a deaerator for degassing the cleaning liquid. A work holding jig is provided at a predetermined position above the ultrasonic vibrator. The ultrasonic vibrator can oscillate ultrasonic waves having a frequency of 1 to 5 MHz. The dissolved oxygen amount can be degassed to 3 mg / l or less, and the work holding jig holds the work with micro holes vertically oriented corresponding to the position almost directly above the ultrasonic vibrator. And a guide hole having a hole diameter tapered downwardly penetrating vertically.
[0006]
Then, as in claim 3, the ultrasonic vibrator that oscillates ultrasonic waves having a frequency of 1 to 5 MHz and a cleaning liquid that can be degassed by a deaerator are housed in the cleaning tank, and are placed above the ultrasonic vibrator. The workpiece having the vertically oriented microholes is positioned and held substantially immediately above the ultrasonic vibrator by the provided workpiece holding jig, and the ultrasonic pressure is applied while the dissolved oxygen amount of the cleaning liquid is reduced to 3 mg / l or less. By operating the vibrator, a jet of the cleaning liquid is blown up toward the work, and the cleaning liquid is passed through the fine holes to clean the work.
Then, the burrs and foreign substances in the micropores are removed by the momentum when the cleaning liquid passes. At this time, if the ultrasonic frequency is set to 1 to 5 MHz and the dissolved oxygen amount of the cleaning liquid is set to 3 mg / l or less, for example, Even if the work is positioned at a position above the level of the cleaning liquid, the momentum of the jet increases and reaches, and the cleaning liquid that has passed through the fine holes can be further sprayed by 30 cm or more, which is extremely effective. Can be washed.
For this reason, fine adjustment of the liquid level, such as when immersing a part of the lower end side of the work in the cleaning liquid, is not required, and since the work holding jig does not enter the cleaning liquid, maintenance is easy. Become.
Incidentally, a part of the lower end side of the work may be immersed in the cleaning liquid, but in this case, if the upper exit side of the micropore is exposed on the liquid surface, the momentum of the jet is maintained. Preferred.
[0007]
In addition, if a holding hole and a tapered guide hole are provided vertically through a work holding jig so that the cleaning liquid enters the fine hole through the guide hole, the cleaning liquid tends to become mist-like. The jet can be suppressed, and the jet can be effectively concentrated at the inlet of the fine hole.
[0008]
In the present invention, the taper angle of the guide hole is set to 60 degrees or more.
By setting the taper angle to 60 degrees or more in this way, the concentration of the jet at the inlet of the fine hole can be increased, and at the same time, the problem that air is mixed into the cleaning liquid in the guide hole can be prevented.
[0009]
Further, in the present invention, the quality of the cleaning is determined by detecting the swaying or split state of the liquid column of the jet flowing upward through the fine holes of the work.
Here, when the jet flows upward through the fine holes of the work, it is possible to know the momentum by the swaying or splitting state of the liquid column, for example, the liquid column rises in a clean form to a predetermined height Cleaning is good. If the liquid column shakes or splits on the way, cleaning is poor. Therefore, these are detected to determine the quality of cleaning.
Incidentally, for example, an optical sensor or the like can be used as a means for detecting the swinging or splitting state of the liquid column.
[0010]
Further, in the present invention, after cleaning with the cleaning liquid, the micropores are rinsed by passing a rinsing liquid through the same method as in the case of cleaning.
Then, for example, in the case where the cleaning liquid has a property that is difficult to dry, the cleaning liquid that has entered the inside of the micropores is replaced with a rinse liquid such as pure water, which is easy to dry, so that it can be dried earlier.
[0011]
Further, in the present invention, after cleaning with the cleaning liquid or rinsing with a rinsing liquid, air is passed through the fine holes to dry.
It is preferable to circulate the air of the fine pores in this way, because the drying can be further promoted.
Here, the air may be air at room temperature, but it is more preferable to use hot air or hot air, and as a means for passing air, for example, a vacuum suction method is used in which one end of the opening of the fine hole is evacuated. It may be made to pass through, or may be made to pass by a pressurized pressure feeding system in which pressurized air is fed from one end of the opening.
[0012]
Further, in the present invention, the work held by the work holding jig is immersed in the cleaning liquid to perform ultrasonic cleaning during or after the cleaning in which the jet of the cleaning liquid is passed through the fine holes.
Such a method is effective, for example, in a case where the foreign matter adheres to the periphery of the blowout portion of the hole and does not separate simply by passing the jet through the fine hole.In such a case, the work is immersed in the cleaning liquid. Then, it can be easily removed by ultrasonic cleaning.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
An embodiment of the present invention will be described with reference to the accompanying drawings.
Here, FIG. 1 is a schematic view of an example of the present cleaning apparatus, showing an example in which a work holding jig is arranged on the surface of a cleaning liquid, FIG. 2 is an explanatory view of a cleaning method in the apparatus, and FIG. And FIG. 4 is an explanatory view of an example when drying is performed, and FIG. 5 is an effect of tilting the work holding jig when the work holding jig is arranged on the surface of the cleaning liquid. FIG. 6 is an explanatory view of a case where the work is immersed in a cleaning liquid and ultrasonically cleaned after cleaning by the method of FIG. 2, and FIG. 7 is a part of the lower part of the work holding jig immersed in the cleaning liquid. It is explanatory drawing in the case of making it wash | clean.
[0014]
The cleaning technique according to the present invention has been developed as a technique suitable for cleaning a small work having a fine hole, such as a ferrule used for connector connection of an optical fiber, for example. And a jet of a cleaning liquid generated by an ultrasonic vibrator that oscillates an ultrasonic wave of 1 to 5 MHz is passed through a fine hole of the work through a guide hole of a work holding jig formed below the holding hole. It is characterized by washing.
Incidentally, the workpiece W (ferrule) in the present embodiment has, for example, an axial length of about 10.5 mm and a diameter of about 2.5 mm. As shown in FIG. The fine hole b is formed, and the diameter of the fine hole b is about 0.125 mm. At one end of the fine hole b, there is provided a V hole whose diameter increases outward.
[0015]
Here, as an example of the cleaning device, a work holding jig is disposed at a position above the cleaning liquid and away from the liquid surface. As shown in FIG. 1, the cleaning tank 1 for storing the cleaning liquid E includes an overflow tank. In addition to the part 1a, a deaerator 2 for deaeration from the cleaning liquid E is connected next to the part 1a, and a work holding jig 3 for holding a plurality of works W is provided above the cleaning tank 1. It is provided by support means (not shown). As shown in FIG. 2, the work holding jig 3 is provided with a holding hole 3h capable of accommodating the work W and a guide hole 3g below the holding hole 3h. The guide hole 3g has a substantially conical shape in which the hole diameter is tapered downward, and an ultrasonic oscillator 4 is provided in the cleaning liquid E immediately below the holding hole 3h and the guide hole 3g. .
[0016]
The degassing device 2 includes a degassing cylinder into which the cleaning liquid E in the cleaning tank 1 is fed, a vacuum pump for degassing the gas in the detergent liquid E in the degassing cylinder, and a degassing cleaning liquid E in the cleaning tank 1. A circulation pump or the like for returning the cleaning solution is provided, and the cleaning solution E in the cleaning bath 1 is evacuated while being circulated through the deaerator 2 so that the dissolved oxygen amount of the cleaning solution in the cleaning bath 1 is reduced to 3 mg / l or less. It has to be noticeable.
[0017]
In the embodiment, the work holding jig 3 is disposed at a position where the height t from the liquid surface El is about 2 to 10 mm, and the holding hole 3h is formed at the lower end of the work W in which the fine holes b are vertically oriented. The holding portion 3h is shaped and sized so that the portion can be accommodated, and when the work W is loaded into the holding hole 3h, the V-hole portion is positioned downward. The work W inserted into the holding hole 3h is positioned by a fixing means (not shown) so as not to come out upward.
The taper angle θ of the substantially conical guide hole 3g is set to 60 degrees or more, so that the degree of concentration of the jet at the entrance of the fine hole can be increased, and the cleaning liquid in the guide hole is supplied with air. Is hardly mixed.
The hole diameter of the portion where the opening area at the upper end of the guide hole 3g is narrowed is slightly larger than the diameter of the end of the V hole of the work W.
[0018]
The ultrasonic vibrator 4 is composed of a disk-shaped piezoelectric element having a thickness of about 3 mm and a diameter of 20 to 30 mm, and is capable of oscillating ultrasonic waves having a frequency of 1 to 5 MHz when a voltage is applied. When ultrasonic waves are oscillated in the cleaning liquid E, a large number of spherical vacuum nuclei are generated, and these vacuum nuclei move at a high speed in the vertical direction while repeating generation and disappearance, and the effect of the sound pressure is combined. Thus, the cleaning liquid E directly above the ultrasonic vibrator 4 is jetted upward as a jet.
As described above, in the present embodiment, the ultrasonic vibrator 4 is provided just below the holding hole 3h and the guide hole 3g of the work holding jig 3 at a position where the depth d from the liquid surface El is about 45 to 65 mm. It is arranged in.
[0019]
In the cleaning apparatus as described above, after the work is inserted into the holding hole 3h of the work holding jig 3 and positioned, the ultrasonic output 20 to 30 W in the cleaning liquid E degassed to a dissolved oxygen amount of 3 mg / l or less. When the ultrasonic vibrator 4 is operated at a frequency of 1 to 5 MHz, the cleaning liquid E immediately above is spouted upward from the liquid surface El, and is concentrated on the V hole portion of the fine hole b by the guide hole 3g. From the upper outlet part b, the jet became a jet having a height of 50 to 60 cm or more, and the jet was blown up. All the cleaning results were good.
At this time, it was also confirmed that when the dissolved oxygen amount of the cleaning liquid E was 3 mg / l or more, the jetting amount and the momentum of the jet decreased, and defective products were generated in the cleaning product.
Further, it was also confirmed that when the hole diameter of the fine holes b was about 5 mmφ or less, all of them were effective.
[0020]
By the way, it was also confirmed that the quality of cleaning can be determined by monitoring the state of the jet.
That is, when the liquid that has passed through the fine holes b becomes a liquid column having a fine diameter in which the height range of about 10 to 50 mm is quite stable, as shown in FIG. As shown in FIG. 3B, when the liquid column passing through the fine holes b fluctuates or splits, the cleaning is often defective.
[0021]
For this reason, as shown in FIG. 3C, for example, a plurality of optical sensors x, y, and z are disposed at a height of about 30 mm from the outlet of the fine hole b, and the optical sensor x is a liquid column. , And the other optical sensors y and z are located in the vicinity of the liquid column.
Then, for example, in the case of a tact time of 60 seconds, it is confirmed that the optical sensor x detects the liquid column 10 seconds after the ultrasonic vibrator 4 is operated, and then, after 30 seconds, the other optical sensors y and z are activated. It is checked that if these do not detect the liquid, they are non-defective, and if the optical sensors y and z detect the liquid, they are determined to be defective. In addition, when it is determined that the product is defective, after confirming that the optical sensor x detects the liquid column 50 seconds later, the other optical sensors y and z are checked 60 seconds later to detect the liquid. If not, it is determined to be non-defective, and if detected, it is determined to be non-defective, etc.
[0022]
If the quality is determined in such a manner, a defective product can be found at an early stage, and the subsequent corrective action can be taken at an early stage.
[0023]
After the cleaning with the cleaning liquid E is completed, it may be preferable to perform rinsing (rinsing) with a rinsing liquid. This is particularly the case where the cleaning liquid E has a property that it is difficult to dry. In this case, the drying liquid is replaced with a rinse liquid that dries easily to speed up the drying. The rinsing with a rinsing liquid is performed in the same manner as the rinsing.
[0024]
When washing or rinsing is completed, air is circulated through the fine holes b to dry.
For example, as shown in FIG. 4, after drying the periphery of the guide hole 3 g of the work holding jig 3 with the sealing member 5, the lower surface side internal area A of the work holding jig 3 is evacuated, By supplying hot air to the upper surface side region B of the work holding jig 3, a method of flowing hot air through the fine holes b by evacuation can be adopted.
Needless to say, the air may be hot air or air at normal temperature, or air may be supplied through the fine holes b by supplying pressurized air.
[0025]
By the way, when the work holding jig 3 is disposed above the level of the cleaning liquid as described above, if the work holding jig 3 is tilted, the cleaning efficiency can be further increased, and this is illustrated in FIG. 5 will be described.
[0026]
That is, as shown in FIG. 5 (a), when the work holding jig 3 is in a horizontal position above the liquid surface, even if the cleaning liquid E is degassed, bubbles are generated in the jet flowing into the guide holes 3g. May be mixed, and the cleaning effect of the fine holes b may be reduced. This is presumably because when the jet enters the guide hole 3g, there is no escape for the air present in the guide hole 3g.
In addition, there is a disadvantage that the cleaning liquid E tends to accumulate on the upper surface of the work holding jig 3.
[0027]
Therefore, as shown in FIG. 5B, when the work holding jig 3 is tilted, the air inside becomes easy to escape when the jet flows into the guide hole 3g, and bubbles are mixed in the cleaning liquid E in the guide hole 3g. Such a situation can be suppressed. Further, the cleaning liquid on the upper surface of the work holding jig 3 also easily flows down. Therefore, it is possible to prevent a problem that the cleaning effect is reduced.
Incidentally, the inclination angle β at this time was effective at about 5 to 15 degrees.
[0028]
Next, an embodiment in which the work W is ultrasonically cleaned by immersing the work W in the cleaning liquid E during or after the cleaning in which the jet is passed through the fine holes b of the work W will be described with reference to FIG.
As described above, it is preferable that at least the outlet side of the fine holes b be discharged to the outside of the cleaning liquid E when the jet flows through the fine holes b for cleaning, but in this case, in some cases, when the jet flows, As shown in FIG. 6A, the foreign matter i is not removed while being attached to the periphery of the blowout portion of the fine hole b, and when the jet stops, as shown in FIG. There may be situations that get into it.
[0029]
Therefore, in order to prevent such a problem, the work holding jig 3 is lowered by an elevating means (not shown), and the work W is immersed in the cleaning liquid E while allowing the jet flow to pass through the fine holes b. Is subjected to ultrasonic cleaning by the ultrasonic oscillator 6 disposed in the apparatus. Then, as shown in FIG. 6C, the foreign matter i can be easily removed.
In some cases, it may be effective to immerse the work W in the cleaning liquid E after stopping the jet flow.
[0030]
In the above-described embodiment, the example in which the work holding jig 3 is disposed above the liquid level El of the cleaning liquid E has been described. However, as shown in FIG. The fine holes b can be effectively washed by increasing the force of the jet. However, it is preferable that the exit portion of the fine hole b of the work W faces the liquid surface El of the cleaning liquid E.
[0031]
Note that the present invention is not limited to the above embodiments. Those having substantially the same configuration as those described in the claims of the present invention and exhibiting the same functions and effects belong to the technical scope of the present invention.
For example, the work W may have a fine hole other than the ferrule, and the positions of the work holding jig 3 and the ultrasonic vibrator 4 are just examples.
[0032]
【The invention's effect】
As described above, the method for cleaning a work having micropores according to the present invention includes an ultrasonic vibrator that oscillates an ultrasonic wave having a frequency of 1 to 5 MHz and a cleaning liquid that can be degassed by a deaerator is accommodated in a cleaning tank. A work holding jig disposed above the ultrasonic vibrator positions and holds the work having the vertically oriented fine holes almost directly above the ultrasonic vibrator, and reduces the dissolved oxygen amount of the cleaning liquid to 3 mg / l. By operating the ultrasonic vibrator while degassing below, a jet of the cleaning liquid is blown up toward the work, which is extremely efficient as compared with a conventional manual cleaning method, and Even when the work holding jig is arranged at a position higher than the liquid level of the cleaning liquid, the cleaning can be effectively performed.
At this time, if the taper angle of the guide hole is set to 60 degrees or more, the jet can be concentrated on the fine holes while maintaining the force of the jet jetted from the liquid surface, and air is mixed into the cleaning liquid. Can be prevented.
[0033]
In addition, if the quality of cleaning is determined based on the swaying or split state of the liquid column of the jet that jets upward through the fine holes in the work, the quality can be determined at an early stage, and subsequent measures can be taken at an early stage. You can do it.
Also, after washing with the washing liquid, in the same manner as in the case of washing, the rinsing liquid is passed through the micropores to be rinsed, and at the time of drying, the air is passed through the micropores and dried. If so, it can be dried early.
Furthermore, the cleaning effect can be enhanced by immersing the work in a cleaning liquid and performing ultrasonic cleaning during or after the cleaning in which the jet is passed through the fine holes.
[Brief description of the drawings]
FIG. 1 is an explanatory view showing an example of a configuration of an example of the present cleaning apparatus, in which a work holding jig is arranged on a liquid surface of a cleaning liquid. FIG. 2 is an explanatory view of a cleaning method in the apparatus. FIG. FIG. 4 is an explanatory view of an example of pass / fail and a pass / fail determination method. FIG. 4 is an explanatory view of an example when drying is performed. FIG. 5 is an effect of tilting the work holding jig when the work holding jig is arranged on the surface of the cleaning liquid. FIG. 6 is an explanatory view of a case where the work is immersed in a cleaning liquid and ultrasonically cleaned after cleaning by the method of FIG. 2 [FIG. 7] A part of the lower part of the work holding jig is immersed in the cleaning liquid Explanatory diagram in case of cleaning by letting
DESCRIPTION OF SYMBOLS 1 ... Cleaning tank, 2 ... Deaerator, 3 ... Work holding jig, 3h ... Holding hole, 3g ... Guide hole, 4 ... Ultrasonic vibrator, E ... Cleaning liquid, El ... Liquid surface, W ... Work, b ... Micro holes.

Claims (7)

A cleaning apparatus for cleaning a work having micro holes, a cleaning tank containing an ultrasonic vibrator and a cleaning liquid, a deaerator for deaeration from the cleaning liquid, and an upper part of the ultrasonic vibrator. A work holding jig disposed at a predetermined position, wherein the ultrasonic vibrator is capable of oscillating ultrasonic waves having a frequency of 1 to 5 MHz, and the deaerator is provided with a dissolved oxygen amount of the cleaning liquid. And the work holding jig holds the work in a state where the fine holes are vertically oriented corresponding to the position almost immediately above the ultrasonic vibrator. And a guide hole having a hole diameter tapered downward and vertically penetratingly provided. The apparatus for cleaning a workpiece having fine holes according to claim 1, wherein the taper angle of the guide hole is set to 60 degrees or more. A cleaning method for cleaning a work having micropores by allowing a cleaning liquid to pass through the micropores for cleaning, wherein an ultrasonic vibrator that oscillates ultrasonic waves having a frequency of 1 to 5 MHz and a deaerator are used. A deaerated cleaning liquid is accommodated in a cleaning tank, and a work holding jig disposed above the ultrasonic vibrator is used to place a work having fine holes vertically oriented substantially directly above the ultrasonic vibrator. By operating the ultrasonic vibrator while maintaining the positioning and deaerating the dissolved oxygen amount of the cleaning liquid to 3 mg / l or less, the cleaning liquid jet is blown up toward the workpiece, and the cleaning liquid is supplied into the fine holes. For cleaning a work having fine holes, wherein the work is passed through the substrate. 4. The cleaning of a work having fine holes according to claim 3, wherein the quality of the cleaning is determined by detecting a sway or a split state of a liquid column of a jet flowing upward through the fine holes of the work. Method. 5. The cleaning of the work having fine holes according to claim 3, wherein after the cleaning with the cleaning liquid, a rinsing liquid is passed through the fine holes and rinsed by the same method as in the case of cleaning. 6. Method. The micropore according to any one of claims 3 to 5, wherein the micropore is dried by washing with the cleaning liquid or rinsing with a rinsing liquid and then passing air through the micropore. Cleaning method for workpieces. 7. The ultrasonic cleaning by immersing the work held by the work holding jig in the cleaning liquid during or after the cleaning in which the jet of the cleaning liquid is passed through the fine holes is performed. A method for cleaning a work having micropores according to any one of the preceding claims.

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