JP2007008054A - Nozzle plugging detecting method in information printing apparatus for board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a nozzle plugging detecting method in an information printing apparatus for a board, which can improve the yield by performing direct test print pattern printing for every print board as a product and determining whether the test printed print board is normal or not for every print board to determine only the print board having print failure to be an inferior product, furthermore which dispenses with a testing print board, with reduction in a production cost. <P>SOLUTION: In the nozzle plugging detecting method in an information printing apparatus for a board, a same color ink is ejected from all the nozzles of a direct automatic marking printer for every print board as a product to print the test print pattern having a desired form in a solid state, and whether the printed test print pattern is in the solid state or not is visibly recognized to enable whether the nozzle plugging occurs or not to be determined. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention is an apparatus for displaying symbol mark information such as a board serial number and a part name of an electronic component to be mounted on a printed circuit board by a direct automatic marking printer, so as to eliminate display errors due to clogging of an ink jet. The present invention relates to a nozzle clogging detection method in an information printing apparatus for substrates.

  Conventionally, the information printing of the symbol mark on the printed circuit board has been performed by a silk screen. However, the printing using the silk screen is time consuming and requires a silk screen to be manufactured for each printed circuit board, which is expensive. There was a problem of becoming.

  Therefore, in recent years, a direct automatic marking printer that directly prints on a printed circuit board by an inkjet printing method having a large number of nozzles has been adopted. In this direct automatic marking printing machine, the nozzle that ejects ink can be controlled by a computer, so when printing on printed circuit boards with different symbol mark information, the program can be changed. Since it can respond, it has the merit that the workability can be improved and the cost can be reduced.

  By the way, in such a direct automatic marking printer using an ink jet, there is a problem that ink is clogged at the tip of the nozzle and normal symbol marks cannot be printed. Therefore, there is an invention disclosed in Japanese Patent Application Laid-Open No. 2004-268449.

In the present invention, test printing is performed by ejecting ink from all nozzles onto the test printed circuit board in a dot shape every predetermined time or every predetermined number of sheets. Whether or not the ink is normally ejected from the nozzles is compared with a normal print dot stored in advance.
JP 2004-268449 A

  By the way, in the above-described invention, since test printing is performed every predetermined time or every predetermined number of sheets, clogging occurs within the predetermined time or within the predetermined number of sheets even if the tent printing is normal. When this occurs, normal symbol marks are not printed. Therefore, when nozzle clogging occurs after performing test printing, it is necessary to go back to the previous test printed board and inspect the printing error, so that inspection takes a very long time. When a printing error occurs in a short time or several sheets after the test printing, a considerable number of defective substrates are generated, resulting in a problem that the yield is very poor.

  The present invention is intended to solve the above-described problems, and the object of the present invention is to perform test print pattern printing directly on each printed circuit board as a product and whether or not each printed circuit board that has been test printed is normal. Therefore, even if a printing defect occurs, only the printed circuit board can be made defective, and the yield can be improved. Also, since the test printed circuit board is not required, the product cost can be reduced. The present invention provides a method for detecting nozzle clogging in an information printing apparatus for substrates.

  The nozzle clogging detection method in the substrate information printing apparatus of the present invention is intended to achieve the above-mentioned object, and the means of claim 1 ejects the same color ink from all nozzles of the ink jet for each printed circuit board as a product. It is possible to determine whether nozzle clogging has occurred by printing a test print pattern of a desired shape in a solid shape and visually checking whether the printed test print pattern is in a peta state. It is characterized by.

  According to a second aspect of the present invention, in the first aspect, the solid print pattern is performed before the symbol mark is printed.

  According to a third aspect of the present invention, in the first aspect, the portion on which the solid test print pattern is printed is a discarded substrate portion of a printed circuit board as the product.

  According to a fourth aspect of the present invention, in the first aspect, the solid test print pattern has a quadrangular shape.

  According to a fifth aspect of the present invention, in the first aspect of the invention, light is irradiated along the solid test print pattern, and it is determined that nozzle clogging occurs when a difference occurs in the amount of reflected light due to the nozzle clogging. It is characterized by doing.

  In the present invention, as described above, the same color ink is ejected from all nozzles of the ink jet for each printed circuit board as a product to print a test print pattern of a desired shape in a solid shape, and the printed test print pattern is in a peta state. Since it is possible to determine whether or not nozzle clogging has occurred by visually checking whether or not it is, it is less time-consuming than when checking at a predetermined time or every predetermined number of sheets as in the past. There will be no defects in the printed circuit board as a product.

  In addition, the solid print pattern is formed before the symbol mark is printed, so that the yield of the printed circuit board as a product is improved without causing a defect.

  Furthermore, by setting the portion on which the solid test print pattern is printed as the discarded substrate portion of the printed circuit board as a product, it is possible to deliver a good-looking substrate on which the test print pattern is not printed to the orderer.

  In addition, by making the solid test print pattern square, printing with ink from a large number of nozzles becomes uniform, and it is easy to determine when nozzle clogging has occurred.

  Furthermore, by irradiating light along a solid test print pattern, it is determined that nozzle clogging has occurred when there is a difference in the amount of reflected light due to nozzle clogging. This is advantageous in that it can be detected with a simpler circuit than when clogging is detected and the cost of the product can be reduced.

  In the present invention, nozzle clogging can be determined by ejecting the same color ink from all nozzles of an ink jet for each printed circuit board as a product and printing a test print pattern of a desired shape in a solid form.

The nozzle clogging detection method in the board information printing apparatus according to the present invention will be described below.
A feature of the present invention is that a large number of nozzles are arranged, and ink is ejected from a desired nozzle of the nozzles toward a preset part (such as a part to which electronic components are soldered) of a printed circuit board, Necessary for producing the printed circuit board 1 before printing the symbol mark 1a, during printing of the symbol mark 1a, or after printing in a known direct automatic marking printing machine that prints the characters and designs that are the symbol mark 1a. The same color (generally white) ink is ejected from all the nozzles from the up and down direction in FIGS. 1 and 2 to the discarded substrate (reference numeral 11 shown in FIG. 1) and the empty part of the product as the processing allowance. A square and solid test print mark 11a is printed.

  In this way, when the rectangular test print pattern 11a is printed solidly, when the ink from all the nozzles is ejected normally, the solid state is obtained as shown in FIG. As a result, it can be seen that all nozzles are not clogged, and if even one is clogged, the printed circuit board is not printed as shown in FIG. 11b can be seen. Therefore, it can be seen that the nozzle is clogged.

  In the above description, the test print pattern 11a has a quadrangular shape (rectangular shape). However, the pattern is not limited to a quadrangular shape, but is ejected from nozzles such as a round shape, an elliptical shape, and a triangular shape. If the length of the applied ink is different, it is difficult to distinguish even if the nozzle of the short applied part is not ejected, so the one with the same length from each nozzle, such as a rectangle or square, is better. Easy to judge clogging.

  In addition, although the case where the above-described test print pattern 11a is checked by the operator's eyes to determine whether or not there is a line 11b due to nozzle clogging has been described, the presence or absence of the line 11b may be automatically determined. Is possible.

  Hereinafter, a method for determining whether or not the test print pattern 11a is normal will be described. An optical sensor (for example, attached to an ink jet printer) after the printed circuit board 1 as a product is set in the substrate information printing apparatus (for example, The light emitting diode) is irradiated with light from the optical sensor along the longitudinal direction of the test print pattern 11a as indicated by the arrow in FIG. 2, and the reflected light from the test print pattern 11a is received by a light receiver (for example, a phototransistor). To do.

  Then, it can be determined whether or not the nozzle is clogged by determining whether or not a change in the amount of reflected light received by the light receiving sensor has occurred. That is, when the test print pattern 11a is in a solid state as shown in FIG. 2A, it can be seen that no clogging has occurred since the amount of reflected light from the optical sensor 5 does not change. As shown in 2 (b), when one of the nozzles (there may be a plurality of nozzles) is clogged, the amount of reflected light changes, so that it is understood that clogging has occurred.

  If it is determined that the nozzle is clogged, the inkjet printer is moved to the position of the nozzle cleaning means to clean the nozzle and eliminate the clogging. Then, after eliminating the clogging of the nozzle, the symbol mark is printed again by the ink jet printer, and the operation is completed. On the other hand, when it is determined that the nozzle is not clogged, the symbol mark 1a is printed in the same manner as described above.

  Before printing the symbol mark, the test print pattern 11a is printed to determine whether the nozzle is clogged. If it is determined that the nozzle is clogged, the nozzle cleaning is performed. If the symbol mark is printed after the clogging is eliminated, the printing mistake of the printed board as a product can be eliminated, and the yield due to the defective printed board can be improved.

It is a front view of the printed circuit board which implemented the nozzle clogging detection method concerning this invention. The test print pattern printed on the printed circuit board same as the above is shown, (a) A normal pattern, (b) shows the pattern by nozzle clogging.

Explanation of symbols

1 Printed circuit board 11 Discarded circuit board 11a Test print pattern

Claims (5)

Whether the test print pattern of the desired shape is printed in a solid shape by ejecting the same color ink from all nozzles of the direct automatic marking printer for each printed circuit board as a product, and the printed test print pattern is in a peta state A nozzle clogging detection method in an information printing apparatus for a substrate which makes it possible to determine whether or not nozzle clogging has occurred by visually checking whether or not. 2. The method for detecting clogging of nozzles in an information printing apparatus for a substrate according to claim 1, wherein the solid print pattern is performed before printing of the symbol mark. 2. The method of detecting clogging of nozzles in an information printing apparatus for a substrate according to claim 1, wherein the portion on which the solid test print pattern is printed is a discarded substrate portion of the printed circuit board as the product. 2. The method for detecting clogging of nozzles in an information printing apparatus for a substrate according to claim 1, wherein the solid test print pattern is rectangular. 2. The substrate information according to claim 1, wherein light is irradiated along the solid test print pattern, and it is determined that the nozzle is clogged when a difference occurs in the amount of reflected light due to the nozzle clogging. A method for detecting nozzle clogging in a printing apparatus.

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