JP2002240248A - Screen plate cleaning device employing cleaning liquid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To clean a screen plate stained by using cream solder or the like for a substrate on the screen plate, easily and very efficiently employing cleaning liquid. SOLUTION: A screen plate cleaning device is constituted of an upper cleaning unit A, a lower cleaning unit B and a supporting body C. The unit A is provided elevatably at the upper surface side of the screen plate 1 retained horizontally and is equipped with a first cleaning section 4 provided with an opening part 4A abutted against the upper surface 1A of the screen plate, a cleaning liquid pouring means 4B and an ultrasonic vibrator 3. The unit B is provided elevatably at the lower surface side of the screen plate and is equipped with a second cleaning section 5 provided with an opening part 5A abutted against the lower surface 1B of the screen plate and a cleaning liquid pouring means 5B. The units A, B can be moved integrally into fore-and-rear direction while the unit A is provided with a driving mechanism for reciprocating the vibrator 3 into a direction orthogonal to the moving direction of the same. The screen plate 1 is cleaned by ultrasonic vibration cleaning under a condition that the same is dipped into the cleaning liquid.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for cleaning a screen plate which is indispensable for screen printing, and more particularly to a screen plate which is used for printing paste such as cream solder on a substrate by using a cleaning liquid. The present invention relates to a cleaning type screen plate cleaning device for cleaning.

[0002]

2. Description of the Related Art Conventionally, an apparatus for cleaning a screen plate used for printing a paste printing material such as cream solder on a substrate such as a printed circuit board by spraying and spraying a cleaning liquid on the screen plate is disclosed in, for example, Japanese Utility Model Application Laid-Open Publication No. HEI 9-26095. 5
It is publicly known as disclosed in JP-A-13745, JP-A-10-71705 and the like. Further, a device in which an ultrasonic vibration device is added to such a device is also known.

[0003]

In screen printing, the higher the viscosity of the paste used for printing, the more the paste adheres to the screen plate, especially in and around the pattern openings after the printing process, When the printing is continued while leaving these residues, printing defects such as blurring of printing, blurring, and disconnection are caused. Therefore, when a residue is generated, it is necessary to remove the residue from the screen. The above-described conventionally known cleaning type cleaning apparatus can remove not only the residue attached to the upper and lower surfaces of the screen plate but also the residue attached to the pattern openings by using the cleaning liquid. This is advantageous in comparison with other known cleaning devices adopting a sliding removal method in which a scraper blade or the like is slid in contact with the screen plate to remove a residue attached to the upper or lower surface thereof. . However, in recent years, with the increasing tendency of electronic devices to become smaller, denser, and more highly integrated,
The pattern opening of screen plates used for screen printing, which is performed prior to the surface mounting of electronic components on printed circuit boards, etc., has been increasing in the trend of higher definition and higher density. The reality is that even screen plates with a hole diameter of about 100 microns have appeared. As described above, in screen printing using a screen plate having high-definition and high-density pattern openings, even fine residues and foreign substances that cannot be seen by the naked eye are attached to the pattern openings. Not only adversely affects the print results,
Residues and foreign substances clogged in such fine pattern openings are not easily removed simply by spraying the cleaning liquid in a spray state and cleaning, or simultaneously applying ultrasonic vibration to the screen plate, and It is difficult to remove clogged viscous paste residues and hardened paste residues. A screen that can be easily and extremely efficiently cleaned using a cleaning liquid to remove a dirty screen plate, that is, a screen plate to which a paste such as cream solder adheres and remains as a residue in a pattern opening thereof. Its primary purpose is to provide a plate cleaning device.

[0004]

In order to achieve the above object, a screen plate cleaning apparatus according to the present invention comprises a holding frame for detachably holding a screen plate, and a screen plate horizontally held by the holding frame. An ultrasonic vibrator for imparting vibration is provided inside, and an opening and an opening capable of opening toward the upper surface of the screen plate and abutting against the upper surface of the screen plate to seal the same over a certain range and a cleaning liquid. An upper cleaning unit having a first cleaning unit provided with an injection means and a discharge means, and opened toward the lower surface of the screen plate, and abutted on the lower surface of the screen plate to seal the same over a certain range; A lower cleaning unit having a second cleaning unit having an opening and a cleaning liquid injecting means and a discharging means, and two upper and lower cleaning units capable of moving up and down and integrally moving in the front-rear direction. The screen plate is sandwiched between the opening of the first washing unit and the opening of the second washing unit from the upper surface and the lower surface thereof, and both upper and lower surfaces thereof are within a certain range. The cleaning solution is injected into the first and second cleaning sections through respective cleaning liquid injection means, and the sealed portion of the screen plate is immersed in the cleaning liquid. The ultrasonic vibrator is vibrated while moving the unit integrally, thereby removing dirt due to the paste adhered to the upper and lower surfaces of the screen plate and the inside of the pattern opening, and flowing out into the cleaning liquid. . For other structural features of the screen plate cleaning device according to the present invention, refer to the respective items of claims 2 to 8.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings showing an embodiment of the present invention.

The drawing shows an example of a screen plate cleaning apparatus suitable for cleaning the screen plate contaminated with residues by using the present invention for screen printing of cream solder on a printed circuit board. The screen plate cleaning device is operated so as to sandwich the holding plate 2 as holding means for detachably holding the screen plate 1 and the screen plate 1 horizontally held by the holding frame during cleaning from the upper surface side and the lower surface side. Upper cleaning unit and lower cleaning unit B
And a support C that supports the upper and lower cleaning units so as to be able to move up and down and move integrally in the front-rear direction.

In the screen plate cleaning apparatus according to the present invention, the upper cleaning unit A includes an ultrasonic vibrator 3 for applying vibration to the screen plate 1 horizontally held by the holding frame 2 and the screen. An opening 4A which opens toward the upper surface 1A of the plate, and which is in contact with the upper surface 1A of the screen plate to seal it over a certain range, is provided with an opening 4A for washing liquid and a first means 4C for discharging the cleaning liquid. The lower cleaning unit B includes the cleaning unit 4 and the screen plate 1.
Of the screen plate lower surface 1
B and an opening 5A for injecting the cleaning liquid and a discharging means 5C for abutting against and sealing over a certain range.
The screen plate 1 is sandwiched between the opening 4A of the first washing unit 4 and the opening 5A of the second washing unit 5 from the upper surface and the lower surface thereof. The upper and lower surfaces 1A, 1B are sealed over a certain range, and the cleaning liquid is injected into the first and second cleaning units 4, 5 through the respective cleaning liquid injection means 4B, 5B. 1 is immersed in a cleaning liquid, and in this state, the ultrasonic vibrator 3 is vibrated while the cleaning units A and B are integrally moved in the direction of arrow X which is the cleaning direction, that is, forward. This removes dirt from the paste adhering to the upper and lower surfaces 1A and 1B and the pattern openings 1C of the screen plate, and diffuses and flows out into the cleaning liquid.

In the example shown in the figure, the first cleaning section 4 and the second cleaning section 5 are disposed at positions facing each other across the screen plate 1 of the two upper and lower cleaning units A and B. , On the rear side of each of the first and second cleaning units 4 and 5,
As the two cleaning units A and B move forward, the ultrasonic vibrator 3 moves on the upper surface 1A and the lower surface 1B of the screen plate 1 while moving integrally with the first and second cleaning units 4 and 5. Sliding removing means 6 and 7 are provided respectively for sliding removing the paste residue remaining after the ultrasonic vibration cleaning in a state of being immersed in the cleaning liquid. It is desirable that these sliding removal means 6 and 7 are made of a hard material (alloy, hard resin, or the like) having a high corrosion resistance, rigidity, elasticity, and the like in a relatively thin spatula shape. In the illustrated example, each of them is made of a spatula made of a relatively thin strip-shaped steel plate, and the spatula 6A serving as the sliding removal means 6 of the upper cleaning unit A is a first cleaning. The first suction part 8 connected to the rear part of the part 4 is directed obliquely downward and forward, and the spatula-shaped body 7A as the sliding removal means 7 of the lower cleaning unit B is provided on the rear side of the second cleaning part 5. The second suction portions 9 are connected to each other and extend obliquely upward and forward. A first air jet nozzle unit 10 as a drying unit for spraying dry air onto a cleaning liquid attached to the screen plate 1 by washing with drying air is provided at a rear side or a rear side of each of the suction units 8 and 9 and a second air jet nozzle unit. Are provided respectively.

The first cleaning section 4, the first suction section 8 and the first air jet nozzle section 10 are fixed to a bracket arm 13 integral with a frame 12 attached to the support C so as to be able to move up and down. Of the upper cleaning unit A as a structural body. Similarly, the second cleaning unit 5, the second suction unit 9, and the second air ejection nozzle unit 11 are also fixed to a bracket arm 15 integrated with a frame 14 attached to the support C so as to be able to move up and down. The lower cleaning unit B as a structure is configured.

In the illustrated example, the first cleaning section 4 includes a front wall 16A and left and right side walls 16A as shown in FIGS.
B, 16C, and a rectangular frame 16 extending in the left-right direction and formed of the spatula 6A also having a function as a rear wall, and the bottom surface thereof defines an opening 5A of the cleaning unit 4. . Then, the drain port 4 as a cleaning liquid discharging means is provided between a lower portion of the rear end surface of the side walls 16B and 16C and a lower portion of the front wall 8A of the suction portion 8 adjacent to the rear end surface.
C is formed. In addition, the front wall 16A is provided with an inlet 4B serving as a means for injecting the above-described cleaning liquid, inwardly. As shown in FIGS. 8 and 9, the second cleaning unit 5 is formed in the shape of a flat rectangular dish-shaped container with a shallow bottom, and the opening 5A has a front wall similar to the first cleaning unit 4. The portion is defined by the portion 17A, the left and right side wall portions 17B and 17C, and the above-mentioned spatula-shaped body 7A which also functions as a rear wall portion. At the front of the cleaning unit 5, an inlet 5B as a means for injecting a cleaning liquid is opened inward, and at the rear, a drain 5C as a means for discharging the cleaning liquid is directed upward. It is open. This drain 5
C also serves as a suction port 9A of the second suction unit 9. On the other hand, the suction port 8A of the first suction unit 8 is connected to the front wall 8 of the first suction unit.
A is formed between the lower end of A and the spatula 6A and communicates with the discharge port 4C.

The upper cleaning unit A is provided with a driving mechanism 18 for reciprocating the ultrasonic vibrator in a direction orthogonal to the moving direction thereof, and the driving mechanism 18 uses the vibrator 3 as a slider. It is configured as an offset crank mechanism. The vibrator 3 is operatively connected to an air cylinder 19 so as to be able to move up and down. As shown in FIG. 7, a plurality of circular vibration transmission plates 3 </ b> A, 3 </ b> A, which directly transmit the vibration to the screen plate 1, are provided on the bottom of the vibrator 3.
B and 3C are provided.

A cleaning liquid supply device (not shown) is provided in the cleaning liquid injecting means of each of the cleaning sections 4 and 5, and a cleaning liquid suction section 8 and
A cleaning liquid suction device (not shown) is connected to each of the cleaning liquid suction devices 9. The suction device includes a tank for filtering used cleaning liquid and a device for circulating the filtered cleaning liquid for reuse. ing. In the illustrated example, during the cleaning operation, the cleaning liquid is continuously injected from the supply device into each of the cleaning units 4 and 5 via each of the injection units 4B and 5B, and each of the suction units is suctioned by the suction device. The screen plate 1 is sucked continuously from the suction ports 8A, 9A
Is made to flow in a state of being immersed.

In FIGS. 1 to 7, 8B is a suction duct joint, 10A outlet, 10B is a dry air inlet joint, 11A
Is a jet outlet, 11B is a dry air inlet joint, 18A is a drive air motor of the offset crank mechanism 18, 20 is a washing liquid supply duct joint, 21 and 22 are air flow air supply pipe joints, 23 is a holding member of the vibrator 3, 24 Is a vertical guide member for guiding the oscillator 3 up and down, 25 is a cleaning liquid suction chamber, 2
6 is a suction duct joint, 27 is an overflow liquid accommodation groove,
28 is an overflow liquid outlet, 29 is a draining blade, and 30 is a wiping squeegee. This blade 2
9 and the squeegee 30, as shown in FIG.
An opening 31 communicating with the suction chamber 25 is provided between the blade 29 and the squeegee 30 between the blade 29 and the drying unit 11 in the lower cleaning unit B. It opens toward the lower surface of.
32 is slidably attached to the support C in the vertical direction,
Sliding rods for raising and lowering the upper and lower cleaning units A and B; 33, a cylinder for raising and lowering the upper unit A; 34, a cylinder for raising and lowering the lower unit B; 35, a guide rod for guiding the support C in the front-rear direction The support C is guided by the guide rod 35 and moved in the front-rear direction by a drive mechanism (not shown). As the cleaning liquid, a liquid containing glycol ether or a hydrocarbon as a water-soluble solvent may be used.

The screen plate cleaning device constructed as described above is operated via a control device (not shown). In the operation, first, the screen plate 1 is placed on the holding frame 2. The screen plate 1 is set horizontally, and then an upper cleaning unit (hereinafter, referred to as an upper unit) A and a lower cleaning unit (hereinafter, referred to as a lower unit) B are operated so as to be sandwiched from the upper surface side and the lower surface side of the screen plate 1. The area of the screen plate 1 to be cleaned is sealed from both upper and lower sides over a predetermined range by the lower opening 4A of the first washing unit 4 in the unit A and the upper opening 5A of the second washing unit 5 in the lower unit B. I do.

Next, in this state, the respective cleaning liquid injection means 4 are provided in the first and second cleaning sections 4 and 5.
The cleaning liquid is injected through B and 5B, and the sealed portion of the screen plate 1 is immersed in the injected cleaning liquid. In this state, the upper and lower units A and B are integrally moved in the cleaning direction X. While operating the ultrasonic vibration device, the screen plate 1 is ultrasonically vibrated through the vibrator 3.

When ultrasonic vibration is applied to the screen plate 1 in a state where the screen plate 1 is immersed in the cleaning liquid in the first and second cleaning units 4 and 5 as described above, the screen plate 1 is simply provided as in the prior art. Unlike the case where the screen plate is ultrasonically vibrated in a state where the cleaning liquid is sprayed and sprayed, the screen plate is vibrated in a state in which the cleaning liquid has completely penetrated the many pattern openings of the screen plate. Simultaneously, a wave is continuously generated in the cleaning liquid itself, and the wave acts to continuously wash the screen plate 1. Therefore, the screen plate 1 is combined with the dissolving power of the cleaning liquid containing a solvent. Not only the residue such as cream solder clogged in the pattern opening but also the residue adhered to the upper and lower surfaces and the hardened residue are extremely effectively removed. When the upper and lower units A and B are moved in the cleaning direction, the ultrasonic vibrator 3 is moved integrally with the unit along with the movement of the unit, and is orthogonal to the movement direction of the unit by the offset crank mechanism 18. The screen plate 1 can be vibrated evenly over a wide range since it is reciprocated in the direction in which the screen plate 1 is moved, so that the cleaning effect of the screen plate 1 by the application of ultrasonic vibration is further enhanced.

In the illustrated example, the upper unit A and the lower unit B have first and second cleaning units 4 and 5 respectively.
Spatula-shaped bodies 6A and 7B as means for sliding and removing cream solder residue adhering to the upper and lower surfaces of the screen plate are respectively attached to the rear sides of the cleaning plates 4 and 5, respectively. Since it moves following, it is slid and removed so as to scrape off the residue that could not be completely removed by the vibration cleaning of the ultrasonic vibrator 3, so that the cleaning effect of the screen plate can be further enhanced.

When the residue adhering to the screen plate 1 is removed as described above, the removed residue diffuses into the cleaning liquid in the cleaning sections 4 and 5 and is discharged together with the cleaning liquid. In the upper unit 4, the used cleaning liquid is sucked into the suction port 8A of the suction unit 8 and transferred together with the residue contained therein and the residue attached to the spatula 6A. In the lower unit 5, the used cleaning liquid is sucked into the suction port 9A of the suction section 9 and transferred together with the residue contained therein and the residue attached to the spatula 7A. In the lower unit B, after the vibration removal and the sliding removal of the residue are performed in this way, the draining blade 29 and the wiping squeegee 30 perform the draining and wiping of the dirty cleaning solution attached to the lower surface of the screen plate, respectively. .

Finally, after the cleaning operation as described above has been performed a required number of times, dry air is blown onto the upper and lower surfaces of the screen plate 1 from the air ejection nozzles 10 and 11 to dry the screen plate and finish the cleaning. I do. This completes the cleaning process of the dirty screen plate 1.

As described above, an example of the embodiment of the present invention has been described in detail with reference to the drawings. However, the present invention is not limited to this, and various modifications may be made within the scope of the claims. Can be implemented

Since the present invention is configured as described above, according to the present invention, not only the residue of the cream solder or the like adhering to the upper and lower surfaces of the screen plate, but also the size of the pattern opening of the screen plate regardless of the size of the pattern opening. Residues that adhere to the inner surface and residues that dry or solidify and are difficult to remove can be easily and extremely efficiently removed and cleaned, and the work efficiency and printing accuracy in screen printing of cream solder etc. on substrates And a screen plate cleaning device capable of significantly improving the above.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view of a main part showing a screen plate cleaning device as an example of an embodiment of the present invention, showing a relative positional relationship between an upper unit and a lower unit during a cleaning operation.

FIG. 2 is a front view of the screen plate cleaning device.

FIG. 3 is a right side view of the apparatus of FIG. 2;

FIG. 4 is a perspective view showing a state where the screen plate is set horizontally on a holding frame.

FIG. 5 is a perspective view of an upper unit.

FIG. 6 is a perspective view showing a part of the unit shown in FIG. 5 cut away.

FIG. 7 is a bottom view of the upper unit.

FIG. 8 is a perspective view of a lower unit.

FIG. 9 is a perspective view showing a part of the lower unit cut away.

[Explanation of symbols]

 Reference Signs List A Upper cleaning unit B Lower cleaning unit C Support 1 Screen plate 2 Holding frame 3 Ultrasonic vibrator 3A to 3C Vibration transmission plate 4 First cleaning unit 4A Opening 4B Injecting unit 4C Discharge unit 5 Second cleaning unit 5A Opening 5B Injecting means 5C Ejecting means 6 Sliding removing means 7 Sliding removing means 8 Suction unit 9 Suction unit 10 Air ejection nozzle unit 11 Air ejection nozzle unit 18 Offset crank mechanism

Claims (8)

[Claims] 1. A holding frame for detachably holding a screen plate, an ultrasonic vibrator for horizontally applying vibration to the screen plate held horizontally by the holding frame, and facing an upper surface of the screen plate. An upper cleaning unit including an opening capable of contacting the upper surface of the screen plate and sealing the same over a predetermined range, and a first cleaning unit having a cleaning liquid injection unit and a discharge unit, An opening opening toward the lower surface of the screen plate and contacting the lower surface of the screen plate to seal the same over a certain range; and a second cleaning unit having a cleaning liquid injecting means and a discharging means. A lower cleaning unit, and a support member that supports the upper and lower two cleaning units so as to be able to move up and down and move integrally in the front-rear direction. The upper and lower surfaces are sandwiched between the opening of the first cleaning unit and the opening of the second cleaning unit to a certain extent, and the cleaning liquid is injected into the first and second cleaning units through respective cleaning liquid injection means. Then, the closed portions of the screen plate are immersed in the cleaning solution by injecting the cleaning solution respectively, and in this state, the ultrasonic vibrator is vibrated while moving each of the cleaning units as a unit. A screen plate cleaning device characterized in that dirt due to the paste adhered to the upper and lower surfaces and the inside of the pattern opening is removed and is discharged into the cleaning liquid. 2. The screen plate cleaning apparatus according to claim 1, wherein the upper cleaning unit is provided with a drive mechanism for reciprocating the ultrasonic vibrator in a direction orthogonal to the moving direction. Plate cleaning device. 3. The screen plate cleaning device according to claim 1, wherein a plurality of vibration transmission plates for directly transmitting the vibration to the screen plate are provided on a bottom portion of the ultrasonic vibrator. Screen plate cleaning device. 4. The screen plate cleaning apparatus according to claim 1, wherein the second cleaning unit is formed in a dish-shaped container having a shallow bottom. 5. A cleaning liquid comprising a paste residue remaining on the upper surface and the lower surface of the screen plate at the rear side of each of the first and second cleaning units as the two upper and lower cleaning units move. 5. The screen plate cleaning device according to claim 1, further comprising a slide removing means for removing a slide in a immersed state. 6. The screen plate cleaning device according to claim 5, wherein each sliding removing means is formed of a relatively thin hard spatula. 7. An apparatus in which suction means for sucking the cleaning liquid injected into the inside of each of the first and second cleaning sections is provided on each rear side, and the suction means filters and circulates the used cleaning liquid. The screen plate cleaning device according to any one of claims 1 to 6, further comprising: 8. The apparatus according to claim 1, further comprising a drying unit provided behind each of the first and second cleaning units to dry the cleaning liquid attached to the screen plate by blowing dry air. 7. The screen plate cleaning device according to any one of items 7 to 7.