JP2004268449A - Printing equipment for substrates - Google Patents

Abstract

A printing apparatus for a substrate that can always maintain normal printing quality is realized.
A printing apparatus for a substrate including a print head that prints predetermined information on a printed circuit board by an ink-jet method includes test printing means for causing the print head to perform test printing at predetermined time intervals.
[Selection diagram] Fig. 1

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a substrate printing apparatus for inkjet printing information such as characters and figures on a printed circuit board. More specifically, the present invention relates to an improved substrate printing apparatus for stabilizing print quality and improving reliability.
[0002]
[Prior art]
Information on symbol marks represented by characters, figures, and the like is printed on the printed circuit board. For example, the serial number of the electronic component to be mounted on the board, the circuit identification number, and the like are printed with characters, and the outline shape of the electronic component to be mounted, the positioning mark for the electronic component mounting apparatus, and the like are printed with graphics. The board printing apparatus is an apparatus that prints information such as characters and figures on a printed board.
[0003]
FIG. 7 is a diagram showing a configuration example of a conventional substrate printing apparatus.
In FIG. 7, the stage 11 is formed in a flat plate shape, and a printed circuit board 12 to be printed is placed thereon. The print head 13 moves in the X-axis and Y-axis directions (substrate surface direction) above the stage 11, and prints symbol marks such as characters and bar codes on the printed circuit board 12 by ink jet. The X-axis and Y-axis directions are the substrate surface directions.
The X-axis servo motor 14 moves the print head 13 in the X-axis direction. The X-axis servo motor 14 is a linear motor, and the print head 13 is mounted on a slider (moving part). By driving this linear motor, the print head 13 moves together with the slider.
[0004]
The Y-axis servo motor 15 moves the print head 13 in the Y-axis direction. The Y-axis servo motor 15 is a linear motor, and the X-axis servo motor 14 is attached to a slider. By driving this linear motor, the slider moves, and the X-axis servo motor 14 and the print head 13 move in the Y-axis direction.
The Z-axis servo motor 16 moves the print head 13 in the Z-axis direction (a direction orthogonal to the paper). The Z-axis direction is the height direction of the substrate. The Z-axis servo motor 16 is a linear motor, and a stator (fixed portion) is attached to a slider of the X-axis servo motor 14, and a print head 13 is attached to the slider. By driving this linear motor, the slider moves in the Z-axis direction, and the print head 13 also moves in the Z-axis direction.
[0005]
The X-axis driver 17, the Y-axis driver 18, and the Z-axis driver 19 drive the X-axis servo motor 14, the Y-axis servo motor 15, and the Z-axis servo motor 16, respectively. The controller 20.21.22 controls the X-axis driver 17, the Y-axis driver 18, and the Z-axis driver 19, respectively.
The personal computer 23 sends the X and Y coordinate data of the printing position to the controllers 20 and 21. The controllers 20 and 21 position the print head 13 at the printing position based on the X and Y coordinate data. Further, the personal computer 23 sends data on the position in the Z-axis direction to the controller 22. The controller 22 positions the print head 13 in the Z-axis direction (height position) based on the transmitted data. The gap between the print head 13 and the surface of the printed circuit board is determined. The personal computer 23 sends the data of the symbol mark to be printed to the print head 13.
[0006]
[Patent Document 1]
JP-A-2002-292914
[Problems to be solved by the invention]
However, in the substrate printing apparatus of FIG. 7, when printing is not performed for a long time, the ink at the nozzle outlet of the print head is irradiated with ultraviolet light included in the atmospheric light, and the ink may be solidified. As a result, the nozzles of the print head are clogged, and the print quality is reduced. In addition, when printing is performed continuously for a long period of time, ink particles adhere to the vicinity of the nozzle outlet, and the ink particles may adhere to a printing surface and deteriorate print quality.
In a printing apparatus for a substrate, when print quality deteriorates, production must be interrupted.
[0008]
The present invention has been made in order to solve the above-described problems, and has a print head perform test printing at predetermined time intervals, and by confirming print quality, it is possible to always maintain normal print quality. It is an object of the present invention to realize a printed device for a substrate.
[0009]
[Means for Solving the Problems]
The present invention is a substrate printing apparatus having the following configuration.
[0010]
(1) In a substrate printing apparatus for inkjet printing predetermined information on a printed circuit board,
A substrate printing apparatus comprising test printing means for causing a print head to perform test printing at predetermined time intervals.
[0011]
(2) In a board printing apparatus provided with a print head for printing predetermined information on a printed board by an inkjet method,
A substrate printing apparatus, comprising: test printing means for performing test printing after cleaning the print head every time a predetermined number of sheets are printed.
[0012]
(3) The substrate printing according to (1) or (2), wherein the test printing unit causes all nozzles in the print head to perform an ejection operation during test printing, thereby printing a test print pattern. apparatus.
[0013]
(4) a camera for photographing the test print pattern;
Inspection means for inspecting whether or not the nozzle is clogged from an image taken by the camera;
The substrate printing apparatus according to (3), comprising:
[0014]
(5) The substrate printing apparatus according to (4), further including a cleaning unit that performs ink purge cleaning when a nozzle is clogged as a result of the inspection by the inspection unit.
[0015]
(6) The substrate printing apparatus according to (4), further including a cleaning unit that performs squeegee cleaning when a nozzle is clogged as a result of the inspection by the inspection unit.
[0016]
(7) The substrate printing apparatus according to (4), wherein the cleaning unit moves the print head to a standby position when the nozzle is not clogged as a result of the inspection by the inspection unit.
[0017]
(8) The substrate printing apparatus according to (5) or (6), wherein the test printing unit prints a test print pattern again after performing ink purge cleaning or squeegee cleaning.
[0018]
(9) The board printing apparatus according to (8), wherein the test printing means generates an alarm when nozzles are still clogged as a result of printing the test print pattern again.
[0019]
(10) The substrate printing apparatus according to (8), wherein the test printing means generates an alarm when nozzles are still clogged as a result of printing the test print pattern a predetermined number of times.
[0020]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be described in detail with reference to the drawings.
FIG. 1 is a configuration diagram showing one embodiment of the present invention. In FIG. 1, the same components as those described above are denoted by the same reference numerals.
[0021]
FIG. 1 shows a state when test printing is performed. A test printing substrate 31 is placed on the stage 11. When performing normal printing, a substrate on which a symbol mark is to be printed is placed on the stage 11.
The camera 32 is mounted on the print head 13. The camera 32 is provided for inspecting a printing result and for alignment of a substrate.
The ink pad 33 and the squeegee 34 are provided in the movement area of the print head 13. The print head 13 ejects ink to the ink pad 33 when performing ink purge cleaning. When performing squeegee cleaning, the print head 13 is rubbed against the squeegee.
[0022]
In FIG. 1, the personal computer 30 has a test printing means 41, a timer 42, a sheet number coefficient means 43, an inspection means 44, and a cleaning means 45 in addition to having the functions of the personal computer 23 of FIG.
The test printing unit 41 causes the print head 13 to perform test printing every predetermined time or every time a predetermined number of sheets are printed.
[0023]
The timer 42 is set to a value corresponding to a predetermined time. When the timer 42 counts for the predetermined time, the timer is up and a test print command is issued to the test printing means 41. The test printing means 41 starts test printing based on this command.
The number counting means 43 counts the number of printed substrates, and issues a squeegee cleaning command to the test printing means 41 when the counted number reaches a predetermined number. The test printing means 41 starts squeegee cleaning based on this command.
[0024]
The camera 32 captures an image of the test print pattern printed on the test print substrate 31. The inspection unit 44 inspects the nozzle 32 of the print head 13 for clogging based on a test print pattern taken by the camera 32.
The cleaning unit 45 performs ink purge cleaning and squeegee cleaning when the nozzle is clogged as a result of the inspection. As a result of the inspection, when there is no clogging of the nozzle, the print head 13 is moved to the standby position.
[0025]
In the set time mode, the test printing means 41 performs test printing at every set time. At this time, the timer 42 triggers a test print. When the printing is intermittent and the interval between printing is long, the set time mode is set to prevent the ink of the nozzles from solidifying.
In the set number mode, the test printing unit 41 performs squeegee cleaning every time a predetermined number of sheets are printed. At this time, the number counting means 43 triggers squeegee cleaning. When ink droplets attached to the nozzles become large during continuous printing, squeegee cleaning is performed to remove the ink particles.
[0026]
The operation of the apparatus shown in FIG. 1 will be described. FIG. 2 is a flowchart showing an operation procedure when operating in the set time mode. The processing will be described according to the order of steps in the flowchart.
(A1) The test printing unit 41 determines whether the set time has elapsed. This is determined based on whether or not a test print command has been issued from the timer 42.
(A2) The test printing unit 41 causes the print head 13 to perform test printing when the set time has elapsed.
[0027]
FIG. 3 is an explanatory diagram of test printing.
The test printing is a printing operation in which all nozzles in the print head 13 perform an ejection operation to print a test print pattern. The test print pattern is printed on the test print substrate 31. The print head 13 has nozzles arranged in a matrix. After the test printing, a matrix dot pattern is printed on the test printing substrate 31. The nozzle is clogged in the part where the dot is missing in the print pattern. In the example of the figure, the dot is missing in the portion of D. The camera 32 photographs the dot pattern on the test printing substrate 31.
[0028]
(A3) Returning to FIG. 2, the inspection unit 44 determines whether or not the nozzles of the print head 13 are clogged from the image captured by the camera 3.
(A4) When the inspection result of the inspection unit 44 does not cause clogging of the nozzle, the print head 13 is moved to the standby position.
(A5) If the inspection result of the inspection means 44 indicates that the nozzle is clogged, ink purge cleaning is performed.
[0029]
FIG. 4 is an explanatory diagram of the ink purge cleaning.
When performing ink purge cleaning, the print head 13 moves to the position of the ink pad 33. Then, the ink is ejected to the ink pad 33. At this time, ink is ejected by applying pressure to the print head 13. The amount of ink used at this time is, for example, about 1 cc for 256 nozzles.
[0030]
(A6) Returning to FIG. 2, squeegee cleaning is performed after ink purge cleaning.
[0031]
FIG. 5 is an explanatory diagram of squeegee cleaning.
5A is a diagram viewed from the front of the print head, and FIG. 5B is a diagram viewed from the side of the print head. In the squeegee cleaning, the print head 13 moves in the E direction, rubs the nozzle portion of the print head against the squeegee 34, and scrapes the ink particles on the nozzles.
[0032]
(A7) Returning to FIG. 2, test printing is performed after squeegee cleaning is performed.
(A8) The inspection means 44 inspects whether or not the nozzle is clogged based on the result of the test printing. If the inspection result indicates that the nozzles are not clogged, the print head 13 is moved to the standby position.
[0033]
(A9) If the test result indicates that the nozzles are clogged, the test printing unit 41 determines whether the number of times of test printing has reached N. N is an integer of 2 or more, for example. The number of test prints is counted by the test printing unit 41.
If the number of test prints has not reached N, the test printing unit 41 returns to process A5 and performs ink purge cleaning. If the number of test prints has reached N, the process ends. In this case, the nozzles are still clogged after performing the test printing N times. In this case, an alarm may be generated.
In this way, test printing is performed for each set time.
[0034]
FIG. 6 is a flowchart showing the operation procedure when operating in the set number mode.
(B1) The test printing unit 41 determines whether or not the set number has been printed. This is determined based on whether or not a squeegee cleaning command is issued from the number counting means 43.
(B2) The test printing unit 41 performs squeegee cleaning when the set number is printed.
The following processes B3 to B10 are the same as the processes A2 to A9 in FIG.
In this way, every time the set number of sheets are printed, squeegee cleaning is performed and test printing is performed.
[0035]
【The invention's effect】
According to the present invention, the following effects can be obtained.
[0036]
According to the first aspect of the present invention, the print head performs test printing at predetermined time intervals. For this reason, when printing is intermittent and the interval between printing is long, it can prevent that the ink of a nozzle solidifies. Thereby, normal printing quality can be always maintained, and the reliability of the substrate printing apparatus can be improved.
[0037]
According to the second aspect of the present invention, the cleaning is performed each time a predetermined number of prints are printed on the print head. Can be removed. Thereby, normal printing quality can be always maintained, and the reliability of the substrate printing apparatus can be improved.
[0038]
According to the third and fourth aspects of the present invention, the test head is caused to print the test print pattern, and the inspection means inspects the captured image of the printed test print pattern for nozzle clogging. Therefore, the clogging of the nozzle can be accurately detected without relying on visual observation.
[0039]
According to the fifth and sixth aspects of the present invention, when the nozzle is clogged, the ink purge cleaning or the squeegee cleaning is performed, so that the clogged nozzle can be repaired accurately.
[0040]
According to the seventh aspect of the invention, when the nozzle is not clogged, the print head is moved to the standby position, so that the print standby state can be promptly set.
[0041]
According to the eighth aspect of the present invention, since the test print pattern is printed again after the ink purge cleaning or the squeegee cleaning is performed, the effect of the cleaning can be confirmed.
[0042]
According to the ninth and tenth aspects of the present invention, if the test print pattern is printed again or a predetermined number of times, and the nozzle is still clogged, an alarm is generated. Therefore, it is accurately determined that the nozzle clogging has not been solved. I can recognize.
[Brief description of the drawings]
FIG. 1 is a configuration diagram showing one embodiment of the present invention.
FIG. 2 is a diagram illustrating the operation of the present invention.
FIG. 3 is an explanatory diagram of test printing.
FIG. 4 is an explanatory diagram of ink purge cleaning.
FIG. 5 is an explanatory diagram of squeegee cleaning.
FIG. 6 is a diagram illustrating the operation of the present invention.
FIG. 7 is a diagram illustrating a configuration example of a conventional substrate printing apparatus.
[Explanation of symbols]
12 printed circuit board 13 print head 32 camera 33 ink pad 34 squeegee 41 test printing means 44 inspection means 45 cleaning means

Claims (10)

In a substrate printing apparatus provided with a print head that prints predetermined information on a printed circuit board by an inkjet method,
A substrate printing apparatus, comprising: test printing means for causing the print head to perform test printing at predetermined time intervals. In a substrate printing apparatus provided with a print head that prints predetermined information on a printed circuit board by an inkjet method,
A substrate printing apparatus, comprising: test printing means for performing test printing after cleaning the print head every time a predetermined number of sheets are printed. 3. The substrate printing apparatus according to claim 1, wherein the test printing unit causes all nozzles in a print head to perform an ejection operation at the time of test printing to print a test print pattern. 4. A camera for photographing the test print pattern;
Inspection means for inspecting whether or not the nozzle is clogged from an image taken by the camera;
The printing apparatus for a substrate according to claim 3, comprising: 5. The apparatus according to claim 4, further comprising a cleaning unit for performing ink purge cleaning when the nozzle is clogged as a result of the inspection by the inspection unit. 5. The substrate printing apparatus according to claim 4, further comprising a cleaning unit for performing a squeegee cleaning when a nozzle is clogged as a result of the inspection by the inspection unit. 5. The substrate printing apparatus according to claim 4, wherein the cleaning unit moves the print head to a standby position when the nozzle is not clogged as a result of the inspection by the inspection unit. 7. The substrate printing apparatus according to claim 5, wherein the test printing unit prints a test print pattern again after performing ink purge cleaning or squeegee cleaning. 9. The substrate printing apparatus according to claim 8, wherein the test printing unit generates an alarm when nozzles are still clogged as a result of printing the test print pattern again. 9. The substrate printing apparatus according to claim 8, wherein the test printing unit generates an alarm when nozzles are still clogged as a result of printing the test print pattern a predetermined number of times.

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