JPH0634444B2 - Printed circuit board cleaning method and apparatus - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method and apparatus for cleaning a printed circuit board for cleaning a printed circuit board that has been soldered.

[Conventional technology]

Conventionally, a printed circuit board that has been soldered, or a printed circuit board that has been cut with lead wires or lead terminals after it has been soldered, is either water or a solution of detergent, or Freon (a product name of DuPont). The metal powder adhered to the printed circuit board was removed by immersing it in a cleaning liquid consisting of or spraying the cleaning liquid.

[Problems to be Solved by the Invention]

By the way, in the conventional method and apparatus for cleaning a printed circuit board described above, since the traveling printed circuit board is simply immersed in the cleaning liquid stored in the cleaning tank, or sprayed with the cleaning liquid, it is possible to remove flacks or Although it is not possible to completely remove stains such as metal powder adhered by cutting the lead wires, the second and subsequent printed circuit boards are cleaned with a cleaning liquid contaminated with flux and metal powder. There was a problem that it had to be.

Further, in the case of using the Freon vapor, the Freon is expensive, and a part of the heated Freon vapor is discharged to the outside, which is wastefully consumed and the cost of the product rises. However, there is a problem that the working environment is deteriorated and that pollution due to Freon vapor occurs.

The present invention has been made to solve the above-mentioned problems. Large stains such as flacks and metal powder adhered to a printed circuit board are cleaned by a roll brush containing a cleaning solution and after being immersed in a flowing cleaning solution. An object of the present invention is to provide a method and apparatus for cleaning a printed circuit board, in which the cleaning solution is cleaned by a shower and the cleaning solution attached to the printed circuit board is removed each time the cleaning is performed.

[Means for Solving the Problems]

A method for cleaning a printed circuit board according to a first aspect of the present invention is to transfer a printed circuit board, which has been soldered, by a transfer means with a soldering surface as a lower surface and another surface as an upper surface, and a roll brush containing a cleaning liquid. After cleaning the lower surface of the printed circuit board by, to remove the cleaning liquid adhering to the printed circuit board by blowing pressurized air, then lower the printed circuit board and the opposite direction to the running direction of the printed circuit board, When the printed circuit board is immersed in a cleaning liquid that intersects the traveling direction of the printed circuit board and is jetted in a direction parallel to the printed circuit board surface for cleaning, and then when the printed circuit board is raised. A cleaning liquid is sprayed to clean the upper and lower surfaces of the printed circuit board, and then the printed circuit board is attached by spraying pressurized air. The washing solution was removed and then,
After drying the printed circuit board with hot air, it is cooled with cool air.

A printed circuit board cleaning device according to a second aspect of the present invention is a device for cleaning a printed circuit board by sequentially transferring the printed circuit board to a device of each step with a soldering surface as a lower surface and another surface as an upper surface. A brush cleaning device provided with a roll brush for cleaning the lower surface of the printed circuit board in a cleaning tank containing a cleaning liquid; a liquid removing device for removing the cleaning liquid adhering to the printed circuit board with pressurized air; An immersion cleaning tank having a jet pipe for jetting a cleaning liquid in a direction opposite to the substrate transport direction and in a direction intersecting the printed substrate transport direction and at least parallel to the printed circuit board surface; and the printed circuit board. Has ejection pipes for ejecting the cleaning liquid toward the lower surface and the upper surface of the printed circuit board when the liquid is pulled up from the immersion cleaning tank. An immersion / shower cleaning device provided with a shower cleaning device for cleaning with a cleaning liquid for cleaning; a hot-air drying device for drying the cleaning liquid adhering to the printed circuit board with hot air; a cooling device for cooling the heated printed circuit board with cold air Are arranged in order, and the printed circuit board is conveyed in the order of the brush cleaning device, the liquid removing device, the immersion / shower cleaning device, the hot air drying device, and the cooling device, and the immersion / shower cleaning is performed. The apparatus is provided with a conveying means having a mechanism for lowering and soaking the printed circuit board in the liquid in the immersion cleaning tank of the apparatus, and a mechanism for raising and lifting the printed circuit board from the liquid.

[Action]

The method and apparatus for cleaning a printed circuit board according to the present invention cleans the lower surface of the printed circuit board with a roll brush containing a cleaning solution and then removes the cleaning solution adhering to the printed circuit board. Then, after cleaning the printed circuit board with a flowing cleaning solution, the upper surface and the lower surface of the printed circuit board are cleaned with a spraying cleaning solution, then the cleaning solution adhering to the printed circuit board is removed, and the printed circuit board is dried with hot air. Cooling.

[Embodiment] FIG. 1 is a schematic constitutional view showing an embodiment of the present invention, in which 1 is a printed circuit board, 1a is an upper surface, and 1b is a lower surface which is a soldering surface. 2 is a carrier for mounting the printed board 1 and carrying it in the direction of arrow A, 3 is a carrying chain as a means for carrying the printed board 1, and as shown by a chain double-dashed line in the drawing, a dipping / shower described later. Cleaning device 21,
At 41, a disposition structure for descending, horizontal traveling, and ascending traveling is provided. Reference numeral 4 denotes an entire cleaning device for cleaning the printed circuit board 1 after the soldering. Reference numeral 5 is a carry-in port of the printed circuit board 1, 6 is a carry-out port, and 7 is a cleaning liquid. 1
Reference numeral 1 denotes a lower surface 1b which is a soldering surface of the printed circuit board 1.
A brush cleaning device for cleaning the cleaning liquid, 12 a cleaning tank, 13 a roll brush that rotates by containing the cleaning liquid 7, 14 a supply pipe to which the cleaning liquid 7 is supplied, 15 a cleaning tank 12
, A receiving pipe for receiving the cleaning liquid 7 overflowing from the upper part, a discharge pipe 17, a first liquid removing device for removing the cleaning liquid 7 adhering to the printed circuit board 1, a first dipping / shower cleaning device, 22 Is a first immersion cleaning layer of the first immersion / shower cleaning device 21, the details of which are shown in FIG.
2 (a) and 2 (b) shown in FIG. 2 (b), FIG. 2 (a) is a plan view, and FIG. 2 (b) is a sectional view taken along line I-I of FIG. 2 (a). Indicates. In FIGS. 1 and 2 (a) and (b), 23
Is a jet tube of the cleaning liquid 7, and the cleaning liquid 7 is applied to the printed circuit board 1
Jet in the direction of arrow B, which is the opposite direction of the traveling direction (direction of arrow A). Reference numeral 24 denotes a jet pipe of the cleaning liquid 7, which is located below the jet pipe 23 by a height h as shown in FIG. 2B, and the cleaning liquid 7 runs in the traveling direction of the printed circuit board 1 (direction of arrow A).
And jets in a direction parallel to the surface of the printed board 1 (direction of arrow C). In FIG. 1, 25 is a heater for heating the cleaning liquid 7, 26 is a filter, 27 is a circulation pipe through which the cleaning liquid 7 in the first immersion cleaning tank 22 circulates, and 28 is the cleaning liquid 7 in the circulation pipe 27. Jet tube 2
It is a pump that makes the jet flow from 3,24. Reference numeral 29 is a receiving tank for receiving the cleaning liquid 7 overflowing from the inside of the first immersion cleaning tank 22, 30 is a discharge pipe for discharging the cleaning liquid 7 in the receiving tank 29, and 31 is a filter. Reference numeral 32 is a first shower cleaner, and 33, 34 and 35 are all spray pipes for spraying the cleaning liquid 7, and the spray pipe 33 sprays the cleaning liquid 7 toward the lower liquid surface, so that the cleaning liquid 7 is discharged into the first cleaning liquid. It is stored in the immersion cleaning tank 22. The ejection pipe 34 ejects toward the upper surface 1a of the printed circuit board 1 rising in the oblique direction. The ejection pipe 35 ejects toward the lower surface 1b of the traveling printed circuit board 1.
Reference numeral 36 is a second liquid removing device, 41 is a second immersion / shower cleaning device, and the construction thereof is the same as that of the first immersion / shower cleaning device 21 shown in FIGS. 2 (a) and 2 (b). In the second immersion / shower cleaning device 41, 42 is a second immersion cleaning tank, 43 and 44 are jet pipes, 45 is a heater, 46 is a filter, 47 is a circulation pipe, 48 is a pump, 49 is a receiving tank,
50 is a discharge pipe, 51 is a filter, 52 is a second shower cleaner, 53, 54 and 55 are ejection pipes, 56 is a third liquid removing device, 57 is a hot air drying device, 58 is a hot air ejection port, 59 Is a hot air inlet, 60 is the hot air drying device 57.
A cooler for cooling the printed circuit board 1 heated in step 1, 61 is a new solution supply tank for supplying new cleaning solution 7, and 62 is a heater for heating the new cleaning solution 7. 71 is the first,
The entire storage device for storing the cleaning liquid 7 discharged from the second immersion / shower cleaning device 21, 41 is shown as 72, 7
3 is the first and second immersion / shower cleaning devices 21, 4
The first and second storage tanks store the cleaning liquid 7 discharged from the first storage tank 1, and are partitioned by a partition wall 74. 75 is a supply pipe for supplying the cleaning liquid 7 in the first storage tank 72 to the cleaning tank 12 of the brush cleaning device 11, 76 is a pump, and 77 is a second immersion of the cleaning liquid 7 in the second storage tank 73. A supply pipe for supplying the first shower cleaning device 32 of the shower cleaning device 41, 78 is a pump, 79 is a heater, 80 is a receiving tank for receiving the cleaning liquid 7 overflowed from the first storage tank 72, and 81 is A discharge pipe and 82 are the receiving tanks 15 and 8 described above.
The waste liquid storage tank receives the waste liquid of the cleaning liquid 7 discharged from 0 due to contamination. The jet tubes 23 and 43, 24 and 44
Correspond, and the action is the same.

Next, the operation will be described.

The printed circuit board 1 mounted on the carrier 2 and completed the soldering or after the completion of the soldering and having the lead wire or the lead terminal cut is held by the carrier 2 locked by the transport chain 3 and The carrier chain 3 travels in the direction of arrow A and enters the cleaning device 4 from the carry-in port 5. Then, the roll brush 13 of the brush cleaning device 11 cleans the lower surface of the printed circuit board 1 for large contaminants such as flux adhered to the lower surface 1b by flux treatment and metal powder adhered by cutting, and the first liquid removing device 17 removes air. The cleaning liquid 7 is removed by spraying. Next, the printed circuit board 1 is lowered and immersed in the cleaning liquid 7 in the first immersion cleaning tank 22. Here, the jet tube 23
Cleaning liquid 7 that jets in a direction opposite to the traveling direction of the printed circuit board 1; Cleaning liquid 7 which is jetted perpendicularly to the printed circuit board surface in a direction intersecting the traveling direction of
By this, the cleaning liquid 7 in the immersion cleaning layer 22 is agitated, and the cleaning liquid is supplied to the immersion layer 22. Further, in the case of a component mounted on the printed circuit board 1 and having a high height on the circuit board, the component may be partially ejected from the cleaning liquid surface of the immersion cleaning tank 22, but is ejected from the ejection pipe 33. This portion is also washed away by the cleaning liquid, and the upper surface 1a and the lower surface 1b of the printed board 1 are cleaned. Next, when the printed circuit board 1 is lifted from the cleaning liquid 7 of the first immersion cleaning layer 22, the ejection pipes 34 of the first shower cleaning device 32,
The upper surface 1a and the lower surface 1b of the printed circuit board 1 are cleaned with the cleaning liquid 7 jetted from 35. Next, the printed circuit board 1 travels horizontally, and when it enters the second liquid removing device 36, the cleaning liquid 7 is removed by blowing air. Then, the printed circuit board 1 is subjected to the first immersion / shower cleaning device 41 in the first
Cleaning is performed through the same steps as those of the immersion / shower cleaning device 21, and then the cleaning liquid 7 is removed by spraying air into the third liquid removing device 56. Then, it is dried by the hot air that enters the hot air drying device 57 and is ejected from the ejection port 58. The hot air that has dried the printed circuit board 1 enters the suction port 59 and circulates in the hot air drying device 57. Next, the dried printed circuit board 1 is cooled by the cool air blown from the cooler 60 and sent out from the carry-out port 6.

Next, the system through which the cleaning liquid 7 flows will be described with reference to FIGS. 1 and 3.

FIG. 3 is a diagram showing a system in which the cleaning liquid 7 flows, and the same reference numerals as those in FIG. 1 indicate the same parts. 1 to 3,
The new cleaning liquid 7 is stored in the new liquid supply tank 61 and then heated by the heater 62, and the cleaning liquid 7 that has become a warm liquid is the second shower cleaning device 52 of the second immersion / shower cleaning device 41.
After being sent to the
After that, the second immersion cleaning tank 42 is entered. That is, the cleaning liquid 7 is supplied to the immersion cleaning tank 42. The cleaning liquid 7 in the second immersion cleaning tank 42 is jetted from the jet pipes 43 and 44 shown in FIG. 1 by the pump 48, and the jetted cleaning liquid 7 circulates in the second immersion cleaning tank 42. On the other hand, the cleaning liquid 7 overflowing from the second immersion cleaning tank 42 is the second cleaning liquid in the storage tank 71.
Into the storage tank 73. Next, the cleaning liquid 7 in the second storage tank 73 is sent to the first shower cleaning device 32 of the first immersion / shower cleaning device 21 by the pump 78 and then jetted to be used for cleaning the printed circuit board 1. After that, the first immersion cleaning tank 22 is entered. That is, the cleaning liquid 7 is supplied to the immersion cleaning tank 22. The cleaning liquid 7 in the first immersion cleaning tank 22 is pumped by the pump 28 into the jet pipes 23, 24 shown in FIG.
And is circulated in the first immersion cleaning tank 22. Further, the cleaning liquid 7 overflowing from the first immersion cleaning tank 22 is the first
Into the storage tank 72. Next, the cleaning liquid 7 in the first storage tank 72 is supplied to the brush cleaning device 11 by the pump 76. Next, both the cleaning liquid 7 overflowing from the brush cleaning device 11 and the cleaning liquid 7 overflowing from the first storage tank 72 are stored in the waste liquid storage tank 82.

The cleaning liquid 7 overflowing from the second storage tank 73 enters the first storage tank 72.

In this way, the heated new cleaning liquid 7 is supplied to the second immersion / shower cleaning device 41, and the second immersion / shower cleaning device 4 is supplied to the first immersion / shower cleaning device 21.
Cleaning is performed with the cleaning liquid 7 used in 1. Also,
Also in the brush cleaning device 11, cleaning is performed with the cleaning liquid 7 used in the first immersion / shower cleaning device 21.

Further, since the first liquid removing device 17 is provided, the cleaning liquid 7 soiled by the brush cleaning device 11 does not mix into the first immersion / shower cleaning device 21. Further, also in the second liquid removing device 36, the first dipping / shower cleaning device 2
The cleaning liquid 7 contaminated with 1 is completely removed, and the second immersion
It does not mix with the shower cleaning device 41.

〔The invention's effect〕

As described above, according to the first aspect of the present invention, the printed circuit board that has been soldered is carried by the carrying means with the soldering surface as the lower surface and the other surface as the upper surface, and
After cleaning the lower surface of the printed circuit board with a roll brush containing a cleaning solution, the cleaning solution adhering to the printed circuit board is removed by blowing pressurized air, and then the printed circuit board is lowered to the running direction of the printed circuit board. On the other hand, the printed circuit board is immersed in a cleaning liquid that is jetted in the opposite direction and in a direction that intersects the traveling direction of the printed circuit board and is parallel to at least the printed circuit board surface for cleaning, and then, When the printed circuit board is raised, a cleaning liquid is sprayed to clean the lower surface and the upper surface of the printed circuit board, then the cleaning solution adhering to the printed circuit board is removed by spraying pressurized air, and then the printed circuit board is dried with hot air. After that, it is cooled with cool air, so the printed circuit board is completely washed and high quality printed There is an advantage that the plate can be obtained.

A second invention of the present invention is a brush cleaning device in which a cleaning tank containing a cleaning liquid is provided with a roll brush for cleaning the lower surface of the printed circuit board; and the cleaning liquid attached to the printed circuit board is removed by pressurized air. A liquid removing device; a dip having jet nozzles for jetting a cleaning liquid in a direction opposite to the printed circuit board transport direction and in a direction intersecting the printed circuit board transport direction and at least parallel to the printed circuit board surface. It has a cleaning tank and jet pipes for jetting the cleaning liquid toward the lower surface and the upper surface of the printed circuit board when the printed circuit board is pulled up from the immersion cleaning tank, and is cleaned by the cleaning liquid sprayed from these jet tubes. An immersion / shower washing device provided with a shower washing device for performing; a hot air drying device for drying the washing liquid adhering to the printed circuit board with hot air And a cooling device that cools the heated printed circuit board with cold air in that order, the printed circuit board having the brush cleaning device, the liquid removing device, the immersion / shower cleaning device, and the hot air drying device. And a cooling device, and a mechanism for descending and soaking the printed circuit board in the liquid in the immersion cleaning tank of the immersion / shower cleaning device and a mechanism for elevating and lifting the liquid from the liquid. Since the means is provided, large dirt such as flux metal powder adhering to the printed circuit board will not be mixed in the cleaning solution in the next stage, so that the cleaning solution is cleaned every time the printed circuit board is cleaned. As dirt is completely removed,
It has advantages such as low consumption of cleaning liquid and economic efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic configuration diagram showing an embodiment of the present invention, FIG.
(a), (b) shows the 1st immersion washing tank of FIG. 1, FIG. 2 (a) is a top view, FIG. 2 (b) is I of FIG. 2 (a). FIG. 3 is a cross-sectional view taken along line I, and FIG. 3 is a diagram showing a system in which the cleaning liquid flows. In the figure, 1 is a printed circuit board, 1a is an upper surface, 1b is a lower surface, 3
Is a transport chain, 4 is a cleaning device, 7 is a cleaning liquid, 11 is a brush cleaning device, 12 is a cleaning tank, 13 is a roll brush, 1
7 is a first liquid removing device, 21 is a first immersion / shower cleaning device, 22 is a first immersion cleaning tank, 23, 24, 43,
44 is a jet pipe, 32 is a first shower cleaner, 33, 3
4, 35, 53, 54, 55 are jet pipes, 36 is a second liquid removing device, 41 is a second immersion / shower cleaning device, 42
Is a second immersion cleaning tank, 52 is a second shower cleaning device, 5
6 is a third liquid removing device, 57 is a hot air drying device, 60 is a cooler, 61 is a new liquid supply tank, and 62 is a heater.

Claims (2)

[Claims] 1. A printed circuit board after soldering is transferred by a transfer means with a soldering surface as a lower surface and another surface as an upper surface, and after cleaning a lower surface of the printed circuit board by a roll brush containing a cleaning liquid, The cleaning liquid adhering to the printed circuit board is removed by blowing pressurized air, and then the printed circuit board is lowered to cross the direction opposite to the traveling direction of the printed circuit board and the traveling direction of the printed circuit board. And, the printed circuit board is immersed in a cleaning liquid that jets in a direction parallel to the printed circuit board surface for cleaning, and then, when the printed circuit board is raised, the cleaning liquid is sprayed onto the lower surface of the printed circuit board. The upper surface is cleaned, and then the cleaning liquid adhering to the printed circuit board is removed by blowing pressurized air. After the door substrate is dried by hot air, the printed board cleaning method and performing the cooling by cold air. 2. An apparatus for sequentially cleaning a printed circuit board, which has been soldered, with a soldering surface as a lower surface and another surface as an upper surface, to a device for each step by a transfer means and containing a cleaning liquid. A brush cleaning device provided with a roll brush for cleaning the lower surface of the printed circuit board in a cleaning tank; a liquid removing device for removing cleaning liquid adhering to the printed circuit board by pressurized air; Direction, and an immersion cleaning tank having jet pipes for spraying a cleaning liquid in a direction that intersects with the conveyance direction of the printed circuit board and in a direction parallel to the printed circuit board surface, and the printed circuit board was pulled up from the immersion cleaning tank. In this case, there is a shower pipe for ejecting the cleaning liquid toward the lower surface and the upper surface of the printed circuit board, and the shower cleaning is performed by the cleaning liquid ejected from these ejection pipes. A dipping / shower cleaning device provided with a purifier; a hot-air drying device for drying the cleaning liquid adhering to the printed circuit board with hot air; a cooling device for cooling the heated printed circuit board with cold air; Consist of the brush cleaning device, the liquid removing device, the immersion / shower cleaning device, the hot air drying device, and the cooling device in that order, and the immersion cleaning tank of the immersion / shower cleaning device. An apparatus for cleaning a printed circuit board, comprising: a transporting unit having a mechanism for lowering and dipping the printed circuit board in the liquid, and a mechanism for lifting and raising the liquid circuit board in the liquid.