Printing system, printing apparatus, and printing method

Abstract

To provide a printing system capable of suppressing occurrence of printing defect by determining a printing condition while taking a present printing state based on a state, etc., of a solder or a mask into consideration.SOLUTION: A printing system comprises: a printing device 100 which prints a solder using a squeegee for electrodes formed in a plurality of substrates via a mask including a predetermined opening; and an inspection device which inspects a first solder amount printed on a first substrate in the plurality of substrates and transmits a first inspection result to the printing device. The printing device changes a first printing parameter in a plurality of printing parameters based on the first inspection result and prints a solder on a second substrate which is conveyed after the first substrate. The inspection device inspects a second solder amount printed on the second substrate and transmits a second inspection result to the printing device. The printing device changes a second printing parameter, which is different from the first printing parameter, in the plurality of printing parameters based on the second inspection result.SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] The present disclosure relates to a printing system, a printing device, and a printing method for printing solder on a plurality of substrates.

Background Art

[0002] An electronic component mounting system for mounting electronic components on a substrate includes a printing device. The printing device prints paste-like solder on the substrate using a screen mask having a predetermined opening. At this time, the printing device prints the solder based on various printing conditions (printing parameters).

[0003] As a conventional printing parameter acquisition device for acquiring printing parameters, an acquisition unit that acquires printing conditions for specifying members used when printing solder on a substrate, and printing conditions, printing parameters used for controlling the driving of a printing machine, and a database in which the reliability of the printing parameters is stored in association with each other, and outputs printing parameters associated with the printing conditions acquired by the acquisition unit and having a reliability of a predetermined level or more. There is known a printing parameter acquisition device including an output unit (see Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] It should be noted that the content in Japanese in the original text seems to be a bit garbled in the provided " " part. I have translated it as best as possible based on the context, but it might need further clarification if the original intention is different.

[0006] Therefore, the printing parameter acquisition device described in Patent Document 1 refers to a database and determines that the printing quality on the first substrate, on which solder was printed during the first time period, is good if the deviation of the area of ​​solder printed on the first substrate during the first time period from the target value is small. On the other hand, the printing parameter acquisition device determines that the printing quality on the second substrate, on which solder was printed during the second time period, is degraded if the deviation of the area of ​​solder printed on the second substrate during the second time period from the target value is small.

[0007] However, while the printing parameter acquisition device described in Patent Document 1 can output printing parameters based on past performance data stored in a database, it cannot output printing parameters that reflect the current printing state. Therefore, the printing parameter acquisition device described in Patent Document 1 cannot select printing parameters suitable for the current printing state, which may result in printing defects. Furthermore, the current printing state may change depending on the condition of the screen mask used during printing. For example, if dirt accumulates on the screen mask, the amount of solder printed may be excessive.

[0008] This disclosure provides a printing system, a printing apparatus, and a printing method that can determine printing conditions by taking into account the current printing state based on the condition of the solder or mask, and can suppress the occurrence of printing defects. [Means for solving the problem]

[0009] One aspect of the present disclosure is a printing system for printing solder onto a plurality of substrates, comprising: a printing apparatus that prints solder onto electrodes formed on each of the plurality of substrates using a squeegee via a mask having a predetermined opening; and an inspection apparatus that inspects the amount of first solder printed on a first substrate among the plurality of substrates and transmits a first inspection result to the printing apparatus, wherein the printing apparatus changes a first printing parameter from a plurality of printing parameters based on the first inspection result and prints solder on a second substrate transported after the first substrate; the inspection apparatus inspects the amount of second solder printed on the second substrate and transmits a second inspection result to the printing apparatus; and the printing apparatus If the second test result is not an improvement compared to the first test result, the change to the first print parameter is reversed. This is a printing system that modifies a second printing parameter, which is different from the first printing parameter, among several printing parameters.

[0010] Furthermore, one aspect of the present disclosure is a printing apparatus provided upstream of an inspection apparatus that prints solder on a plurality of substrates and inspects the printed solder, comprising: a printing unit that prints solder on electrodes formed on each of the plurality of substrates using a squeegee through a mask having a predetermined opening; a communication unit that receives a second inspection result from the inspection apparatus in which the amount of first solder printed on a first substrate among the plurality of substrates has been inspected; and a control unit that changes a first printing parameter among a plurality of printing parameters based on the first inspection result, wherein the printing unit prints solder on a second substrate transported after the first substrate using the first printing parameter, the communication unit receives a second inspection result from the inspection apparatus in which the amount of second solder printed on the second substrate among the plurality of substrates has been inspected, and the control unit, If the second test result is not an improvement compared to the first test result, the change to the first print parameter is reversed. This is a printing device that changes a second printing parameter, which is different from the first printing parameter, among a group of printing parameters.

[0011] Furthermore, one aspect of the present disclosure is a printing method for printing solder on a plurality of substrates, comprising the steps of: printing solder on an electrode formed on a first substrate among the plurality of substrates using a squeegee through a mask having a predetermined opening; receiving a first inspection result from an inspection device that inspects the printed solder, in which the amount of first solder printed on the first substrate has been inspected; changing a first printing parameter from a plurality of printing parameters based on the first inspection result; using the first printing parameter, printing solder on an electrode formed on a second substrate transported after the first substrate via the mask using the squeegee; and receiving a second inspection result from the inspection device, in which the amount of second solder printed on the second substrate has been inspected. If the second test result is not an improvement compared to the first test result, the change to the first print parameter is reversed. The printing method comprises the step of changing a second printing parameter, which is different from the first printing parameter, among a plurality of printing parameters. [Effects of the Invention]

[0012] According to this disclosure, printing conditions can be determined by taking into account the current printing state based on the condition of the solder or mask, thereby suppressing the occurrence of printing defects. [Brief explanation of the drawing]

[0013] [Figure 1] A schematic diagram showing an example configuration of an electronic component mounting system in the first embodiment of this disclosure. [Figure 2] Figure 1 shows an example of the configuration of the printing apparatus, along the substrate transport direction. (Front view) [Figure 3] A diagram illustrating the printing of solder onto a substrate via a screen mask and the resulting print. [Figure 4] A graph showing an example of the inspection results for the amount of solder printed on a circuit board, as inspected by a printing inspection device. [Figure 5] Block diagram showing a functional configuration example of an electronic component mounting system. [Figure 6] Figure 5 shows a flowchart illustrating an example of the operation flow performed by the print control unit. [Figure 7]Flowchart showing an example of the operation flow of the subroutine shown in FIG. 6 [Figure 8] Diagram showing an example of the procedure for the printing control unit shown in FIG. 5 to change the printing parameters [Figure 9] Diagram for explaining a first specific example showing how the inspection result of the solder amount changes due to the change and adjustment of the printing parameters [Figure 10] Diagram for explaining a second specific example showing how the inspection result of the solder amount changes due to the change and adjustment of the printing parameters

Mode for Carrying Out the Invention

[0014] [[ID=十七]]Hereinafter, embodiments specifically disclosing the printing apparatus and printing method according to the present disclosure will be described in detail with reference to the drawings as appropriate. However, detailed descriptions that are more than necessary may be omitted. For example, detailed descriptions of well-known matters or redundant descriptions of substantially the same configurations may be omitted. This is to avoid making the following description unnecessarily redundant and to facilitate the understanding of those skilled in the art. Also, each of the attached drawings shall be referred to according to the direction of the reference numerals. Note that the attached drawings and the following description are provided for those skilled in the art to fully understand the present disclosure, and it is not intended to limit the subject matter described in the claims thereby.

[0015] In addition, the “section” or “device” referred to in the embodiment is not limited to a physical configuration mechanically realized by hardware alone, but also includes those in which the functions of the configuration are realized by software such as a program. Also, even if the functions of one configuration are realized by two or more physical configurations, or the functions of two or more configurations are realized by, for example, one physical configuration, it does not matter.

[0016] In addition, hereinafter, the conveyance direction of the substrate is defined as the X direction, the direction orthogonal to the X direction in the horizontal plane is defined as the Y direction, and the direction perpendicular to the XY plane is defined as the Z direction. Also, the Z direction may be referred to as the “vertical direction”, the positive side of the Z direction may be referred to as “up”, and the negative side of the Z direction may be referred to as “down”.

[0017] It should be noted that in the translation of item , there is an error in the original text where "十七" is used instead of the correct number. It should be in the original. The translation is adjusted accordingly. (First Embodiment) A first embodiment according to the present disclosure will be described based on FIGS. 1 to 10.

[0018] [Regarding the basic configuration of the electronic component mounting system] Referring to FIG. 1, a basic configuration example of the electronic component mounting system 1 according to the present embodiment will be described. FIG. 1 is a schematic diagram showing a configuration example of the electronic component mounting system 1 in the present embodiment.

[0019] The electronic component mounting system 1 includes a printing device 100, a printing inspection device 200, a management device 300, a work conveyor M3, and mounting devices M4, M5. The electronic component mounting system 1 prints solder SR on each of a plurality of substrates 2 as described later, inspects the printing state, and mounts electronic components on each of the plurality of substrates 2.

[0020] The printing device 100, the printing inspection device 200, the work conveyor M3, and the mounting devices M4, M5 are connected to form an electronic component mounting line and are controlled by the management device 300. Each of the devices of the printing device 100, the printing inspection device 200, and the mounting devices M4, M5 is connected to the management device 300 via a communication network NT.

[0021] The printing device 100 is, for example, a screen printing device, and screen prints paste-like solder SR on electrodes (hereinafter also referred to as "printing sites") for bonding electronic components formed on each of a plurality of substrates 2 sequentially conveyed, thereby printing solder SR on the electrodes.

[0022] The printing inspection device 200 is an SPI (Solder Paste Inspection), and inspects the printing state of non-printed objects (for example, substrates 2) on which solder SR has been printed by the printing device 100 for each of a plurality of substrates 2 sequentially conveyed. The printing inspection device 200 acquires (inspects) the printing state of each of the plurality of substrates 2 and transmits the inspection result to the printing device 100.

[0023] This printing condition includes, for example, the position, height, area, volume, misalignment, area ratio, and volume ratio of the solder SR printed on the printing area of ​​the substrate. The area ratio and volume ratio serve as indicators of the amount of solder. The area ratio indicates the ratio of the area occupied by the solder SR to the size of the printing area in each printing area. The volume ratio indicates the ratio of the amount of solder SR to the size of the printing area in each printing area. In other words, the printing inspection device 200 acquires, for example, the area ratio or volume ratio of the solder SR printed on each substrate 2 as the amount of solder for each substrate 2 being transported as the first, second, ... and transmits the data.

[0024] The printing area is, for example, the area on the upper surface of the electrodes on substrate 2, and is the pattern hole 13h (an example of an opening: see below) of the screen mask 13 (an example of a mask: see below) that contacts the upper surface of substrate 2, as described later.

[0025] The work conveyor M3 transports the substrates 2 that have been determined to have a good print condition to the downstream mounting device M4. Substrates 2 that have been determined to have a poor print condition are removed by the operator after the transport by the work conveyor M3 is stopped. The mounting devices M4 and M5 are electronic component mounting devices that mount electronic components to the electronic component mounting positions on the substrates 2 where solder joints have been formed.

[0026] Subsequently, the substrate 2 with the electronic components mounted is sent to a reflow machine (not shown) and heated according to a predetermined temperature profile. This heating melts the solder particles contained in the solder SR, and the electronic components and the substrate 2 are soldered together. The control device 300 manages each device in the electronic component mounting system 1. The control device 300 may be, for example, any computer or server.

[0027] [About the basic configuration of a printing device] The hardware configuration of the printing apparatus 100 will be described with reference to Figure 2. Figure 2 is a front view showing an example of the configuration of the printing apparatus 100 shown in Figure 1, along the transport direction of the substrate 2.

[0028] As shown in Figure 2, the printing apparatus 100 has the function of printing solder paste (SR), such as solder paste or conductive paste, onto the substrate 2 using a screen mask 13 on which predetermined pattern holes 13h are formed.

[0029] The printing apparatus 100 comprises a substrate holding table 4, a substrate holding table moving mechanism 5, and a substrate transport mechanism 6.

[0030] The substrate transport mechanism 6 continuously receives substrates 2 from an external device located upstream of the printing device 100, transports them into its own device, and positions them. After printing is performed on the substrates 2, the substrate transport mechanism 6 then transports the substrates 2 downstream.

[0031] The substrate holding table 4 clamps, fixes, and holds the substrate 2 that has been transported from the upstream side by the substrate transport mechanism 6. The substrate holding table moving mechanism 5 can move the substrate holding table 4 in the X and Y directions, as well as move (raise and lower) the substrate holding table 4 in the Z direction. The substrate holding table 4 and the substrate holding table moving mechanism 5 operate integrally with a part of the substrate transport mechanism 6.

[0032] The substrate holding table moving mechanism 5 raises the substrate holding table 4 while the substrate 2 is held, bringing the substrate 2 into contact with the screen mask 13. Then, when solder SR is printed on the substrate 2 while it is in contact with the screen mask 13, the substrate holding table moving mechanism 5 lowers the substrate holding table 4 to release the contact with the screen mask 13. This lowering operation (release operation) is also called the "screen release" operation. The substrate holding table moving mechanism 5 is configured to allow adjustment of the screen release speed (hereinafter also referred to as "screen release speed"). That is, the substrate holding table moving mechanism 5 can adjust the magnitude (adjustment) of the screen release speed according to the instructions of the printing control unit 152 (see below) of the printing device 100. As a result, the printing device 100 can print solder SR for each transported substrate 2 by changing the screen release speed, for example, for a substrate 2 to be transported later, based on the inspection results of the printing inspection device 200 (see below).

[0033] Furthermore, the substrate holding table moving mechanism 5 can also rotate the substrate holding table 4 in a predetermined rotational direction θ within the XY plane. Therefore, the substrate holding table 4 is movable in the X direction (bx direction), Y direction (by direction), and Z direction (bz direction), and is also rotatable in the rotational direction θ (bθ direction). Driven by the substrate holding table moving mechanism 5, the substrate holding table 4 adjusts its position and orientation, that is, the position and orientation of the substrate 2, to determine and align the position of the substrate 2 with respect to the screen mask 13 (specifically, the pattern holes 13h of the screen mask 13).

[0034] The substrate 2 is transported from the upstream side by the substrate transport mechanism 6 and positioned at a predetermined location. After printing is performed on the substrate 2, the substrate 2 is then transported downstream by the substrate transport mechanism 6.

[0035] The printing apparatus 100 further comprises a screen mask 13, a print head 14, a print head moving mechanism 15, and a squeegee 16.

[0036] A flexible screen mask 13 is stretched over the mask frame 13a. Multiple pattern holes 13h are formed in the screen mask 13, corresponding to the shape or position of electrodes, etc., to be printed on the substrate 2 (see, for example, Figure 3). Solder SR is supplied onto the screen mask 13 by a paste supply mechanism (not shown). The solder SR contains an adhesive flux. A print head 14 is positioned on the screen mask 13.

[0037] The print head 14 fills the pattern holes 13h with solder SR and prints solder SR onto the substrate 2. The print head 14 also has a squeegee lifting mechanism 17 that raises and lowers the squeegee 16.

[0038] The squeegee 16 consists of a pair of two squeegees 16 arranged along the Y direction. The squeegee 16 is formed in an elongated shape with the X direction as its longitudinal direction. The squeegee 16 moves up and down in the Z direction by the drive of the squeegee lifting mechanism 17. That is, one squeegee 16 moves up and down in the a1 direction, and the other squeegee 16 moves up and down in the a2 direction. As the squeegee 16 descends, it comes into contact with the upper surface of the screen mask 13. The squeegee 16 slides along the upper surface of the screen mask 13 in contact with it, printing solder SR onto the substrate 2 through the pattern holes 13h of the screen mask 13. Then, as the squeegee 16 is raised by the squeegee lifting mechanism 17, the contact of the squeegee 16 with the upper surface of the screen mask 13 is released.

[0039] The squeegee lifting mechanism 17 is configured to allow adjustment of the pressing force of the squeegee 16 against the screen mask 13, i.e., the printing pressure (an example of a printing parameter). That is, the squeegee lifting mechanism 17 can adjust the magnitude (adjustment) of the printing pressure according to the instructions of the printing control unit 152 of the printing device 100. As a result, the printing device 100 can print solder SR by appropriately changing, for example, the printing pressure among multiple printing parameters, for each substrate being transported, based on the inspection results of the printing inspection device 200.

[0040] The print head moving mechanism 15 moves the print head 14 along the Y direction. The print head 14 is freely movable in the Y direction (ay direction) by the drive of the print head moving mechanism 15. As a result, the squeegee 16 attached to the print head 14 moves in the Y direction and prints solder SR onto the substrate 2 through the pattern holes 13h of the screen mask 13.

[0041] The print head movement mechanism 15 is configured to allow adjustment of the sliding speed of the squeegee 16, i.e., the printing speed (an example of a printing parameter). That is, the print head movement mechanism 15 can adjust the magnitude (adjustment) of the printing speed according to the instructions of the printing control unit 152 of the printing device 100. As a result, the printing device 100 can print solder SR by appropriately changing, for example, the printing speed among multiple printing parameters, for each substrate being transported, based on the inspection results of the printing inspection device 200.

[0042] [Regarding solder printing onto circuit boards via screen masks and the resulting prints] Referring to Figures 3 and 4, the printing of solder SR onto the substrate 2 via the screen mask 13 and the printing results will be explained. Figure 3 is a diagram illustrating the printing of solder SR onto the substrate 2 via the screen mask 13 and the printing inspection. Figure 4 is a graph showing an example of the inspection results of the amount of solder printed on the substrate 2, as inspected by the printing inspection device 200.

[0043] The printing apparatus 100 stores information about the printing areas on the substrate 2 in advance, for example, in the storage unit 153 (see below). The information about the printing areas is included, for example, in the production data.

[0044] The printed areas are located on the substrate 2 where solder SR should be printed to solder the terminals of electronic components to the electrodes of the substrate 2, and correspond to the component mounting positions (component mounting points). Furthermore, the printed areas correspond to the positions of the pattern holes 13h of the screen mask 13 during printing (when the screen mask 13 comes into contact with the substrate 2). Therefore, when solder SR is printed in the pattern holes 13h of the screen mask 13, solder SR is printed in the printed areas.

[0045] In screen printing, first, the printing control unit 152 (see below) brings the substrate 2 into contact with the lower surface 13c of the screen mask 13, and performs a squeegeeing operation by sliding the squeegee 16 across the upper surface of the screen mask 13, to which solder SR is supplied, thereby filling the pattern holes 13h with solder SR. After this squeegeeing operation, the printing control unit 152 performs a stencil release operation to separate the substrate 2 from the lower surface 13c of the screen mask 13. As a result of this operation, three-dimensional solder SR corresponding to the inner shape of the pattern holes 13h is printed on each of the printing areas on the upper surface of the substrate 2. Then, the printing inspection device 200 performs a printing inspection on the substrate 2 after the solder SR has been printed.

[0046] In screen printing, the planar position and three-dimensional shape of the solder SR printed on each printed area do not necessarily precisely match the position and inner shape of the pattern hole 13h, and variations may occur due to various factors.

[0047] For example, the ease with which solder SR penetrates into the pattern holes 13h varies depending on the size of the pattern holes 13h of the screen mask 13 (also simply referred to as the hole size). In Figure 3, various sizes of pattern holes 13h are illustrated as examples of the pattern holes 13h of the screen mask 13. In Figure 3, small pattern holes 13h1 and large pattern holes 13h2 are illustrated. Small pattern holes 13h1 are small holes with a hole size less than a predetermined threshold. Large pattern holes 13h2 are large holes with a hole size greater than or equal to a predetermined threshold.

[0048] The printing pressure and printing speed of the squeegee 16 as it slides over the screen mask 13 do not change during printing on one substrate 2. Therefore, the printing pressure (pressing force) and printing speed (squeegeeing speed) of the squeegee 16 are the same for both the small pattern holes 13h1 and the large pattern holes 13h2 of the screen mask 13, but solder SR can enter more easily through the large pattern holes 13h2 than through the small pattern holes 13h1.

[0049] Therefore, the volume ratio or area ratio of solder SR in the small pattern holes 13h1 tends to be larger than that of solder SR in the large pattern holes 13h2. In other words, the printing pressure and printing speed related to the squeegee 16 are included in the printing parameters, and the printing control unit 152 changes the printing parameters based on the inspection results of the printing inspection device 200. By changing these printing parameters, the printing control unit 152 can adaptively control the volume ratio or area ratio of solder SR printed on the substrate 2 that will be transported later. The same applies to the stencil release speed mentioned above. In other words, the stencil release speed is included in the printing parameters, and the printing control unit 152 can adaptively control the volume ratio or area ratio of solder SR printed on the substrate 2 that will be transported later by changing the printing parameters based on the inspection results of the printing inspection device 200.

[0050] Furthermore, for example, if the alignment between the substrate 2 and the screen mask 13 is poor, misalignment of the solder SR on the substrate 2 may occur. In addition, poor printing volume may occur due to poor filling during the squeegeeing operation or poor stencil release during the stencil release operation. Poor printing volume includes "missing" where the three-dimensional shape of the solder SR is partially missing and the amount of solder SR printed (solder volume) is less than the specified amount, and "bleeding" where the amount of solder is excessive and extends beyond the printing area. In this embodiment, poor printing volume is indicated, for example, as a volume ratio or area ratio of solder volume.

[0051] Such misalignment or insufficient printing of the printed solder SR (for example, insufficient or excessive solder) can cause solder joint failures during reflow soldering after the electronic components have been mounted. Therefore, the inspection execution unit 253 (see below) of the printing inspection device 200 inspects the printing state of the solder SR prior to the mounting of electronic components by the mounting devices M4 and M5, and determines whether the printing state is good or bad. The printing inspection device 200 then feeds back the inspection result data, including the misalignment or insufficient printing state, to the printing device 100. The printing device 100 transmits an inspection result transmission command to the printing inspection device 200, and the printing inspection device 200 may provide feedback to the printing device 100 according to this inspection result transmission command, or it may provide feedback to the printing device 100 sequentially once the printing inspection is completed. The inspection result data may include the coordinates, area, height, or volume of the printed solder SR position for each printed area on each substrate 2. The inspection result data may also include information on the positional deviation of the actual printing position relative to the printed area, volume ratio, or area ratio for each printed area on each substrate 2.

[0052] Furthermore, when inspecting for planar misalignment of solder SR, the printing inspection device 200 may take a planar image of the printed substrate 2 using a camera, process the obtained image data to derive two-dimensional data indicating the printed shape, and inspect the printing position of the solder SR based on this two-dimensional data. The printing inspection device 200 may also calculate three-dimensional inspection result data such as solder SR misalignment or insufficient printing amount by integrating this two-dimensional data in the height direction of the printed area. The printing inspection device 200 may also measure the printed substrate 2 in three dimensions using a three-dimensional measuring instrument, and derive inspection results such as solder SR misalignment or insufficient printing amount based on the three-dimensional data obtained from the measurement. The three-dimensional measuring instrument may be installed in the printing inspection device 200.

[0053] Furthermore, the 3D measuring instrument may be moved over the printed substrate 2 to measure the 3D shape of any area of ​​the substrate 2. The inspection execution unit 253 (see below) may then process the measurement data obtained by the 3D measuring instrument to detect the shape and volume of the solder SR printed on the substrate 2 in 3D. Note that the method for deriving the area or volume of the solder SR is not limited to the specific method described in this embodiment, but may be other known methods.

[0054] The printing control unit 152 of the printing apparatus 100 receives feedback of inspection result data and, based on the inspection result data, may change the printing parameters (printing conditions) in addition to the aforementioned printing parameters, such as moving the substrate holding table moving mechanism 5 or the print head 14, which change the relative position between the substrate 2 and the screen mask 13. As a result, the printing apparatus 100 can suppress misalignment of the solder SR.

[0055] Furthermore, the printing control unit 152 receives feedback of inspection result data and controls printing parameters such as printing pressure, printing speed, and stencil release speed based on the inspection result data (e.g., information on volume ratio or area ratio). In this case, the printing control unit 152 sequentially selects (changes) one printing parameter at a time and adaptively maintains or adjusts the magnitude of these printing parameters. The printing device 100 then prints solder SR on the substrate 2 that is subsequently transported under these printing parameter conditions. By sequentially selecting one printing parameter at a time, the printing device 100 can clearly recognize which printing parameter should be set to which value. In this way, the printing device 100 can adaptively control the volume ratio or area ratio of the solder SR printed in the pattern holes 13h of the screen mask 13 so that it converges to a desired range. In the following explanation, volume ratio will be mainly used as the amount of solder, but the same applies if the amount of solder is an area ratio.

[0056] Next, we will explain the frequency distribution analysis of volume ratios based on the test results.

[0057] The printing device 100 acquires inspection result data from the printing inspection device 200, and for each of the substrates 2 sequentially transported by the substrate transport mechanism 6, it acquires multiple volume fractions as solder amounts for each printed area of ​​the substrate 2. Furthermore, the printing device 100 sorts the acquired inspection results into predetermined classes (areas corresponding to volume fractions) and performs frequency distribution analysis (histogram analysis).

[0058] As shown in Figure 4, the printing apparatus 100 may perform this frequency distribution analysis collectively for a predetermined number of substrates 2 that are transported continuously (for example, 5 or 10 consecutive substrates 2) as one group (analysis unit), and create a frequency distribution graph or table for that predetermined number. In this frequency distribution graph, with respect to the inspection result (for example, volume ratio), an OK area, a warning area formed outside the OK area, and an NG area formed outside the warning area are defined. The frequency may be derived for each volume ratio, for example, and is the number of printed areas that have that volume ratio. The frequency may be the total number of each printed area for each volume ratio of the substrate 2 in the analysis unit, or it may be the average number per substrate 2.

[0059] The printing apparatus 100 performs frequency distribution analysis on multiple substrates 2 as a single group. In this case, the printing apparatus 100 may perform frequency distribution analysis on the substrates 2 to be analyzed such that the next group to be analyzed consists only of completely new substrates 2 that are not included in the previous group. Alternatively, the printing apparatus 100 may perform frequency distribution analysis on the substrates 2 to be analyzed such that a portion of the next analysis unit (group to be analyzed) overlaps with the substrates 2 of the previous analysis unit.

[0060] The OK area is an area where the inspection results for each printed area of ​​the substrate 2 are within the desired range, and the solder SR is printed appropriately (good) in the pattern holes 13h. The warning area is an area where the inspection results are outside the desired range, and the solder SR is not printed appropriately in the pattern holes 13h for each printed area of ​​the substrate 2, but the level of inadequacy is within the operational tolerance range of the electronic component mounting system 1. The warning area also serves as an intermediate area between the OK area and the NG area. The NG area is an area where the inspection results are significantly outside the desired range, the solder SR is not printed appropriately in the pattern holes 13h, and the level of inadequacy is higher than in the warning area.

[0061] When the volume ratio of at least one printing site obtained as an inspection result is included in the NG area, the printing control unit 152 of the printing apparatus 100 may stop the operation of the electronic component mounting system 1. When the volume ratio of at least one printing site obtained as an inspection result is included in the warning area, the printing control unit 152 may not stop the operation of the electronic component mounting system 1, but may output a predetermined warning. The output of the warning may include, for example, presenting or transmitting warning information. The output of the warning may be performed, for example, by the display unit 154 (described later) or the speaker 155 (described later) of the printing apparatus 100. Thereby, the printing apparatus 100 can notify an operator or a worker that the print quality is poor, and can prevent the operation of the electronic component mounting system 1 from stopping in advance.

[0062] In the warning area, an upper limit side warning area where the volume ratio is large on the upper limit side and a lower limit side warning area where the volume ratio is small on the lower limit side are provided. Similarly, in the NG area, an upper limit side NG area where the volume ratio is even larger on the upper limit side and a lower limit side NG area where the volume ratio or area ratio is even smaller on the lower limit side are provided.

[0063] For example, the upper limit side warning area is an area where the volume ratio is equal to or greater than the threshold TH11 and less than the threshold TH21 (>TH11). The upper limit side NG area is an area where the volume ratio is equal to or greater than the threshold TH21. Similarly, the lower limit side warning area is an area where the volume ratio or area ratio is equal to or less than the threshold TH12 and greater than the threshold TH22 (<TH12). The lower limit side NG area is an area where the volume ratio or area ratio is equal to or less than the threshold TH22. These thresholds TH11, TH12, TH21, and TH22 are set to coincide with the boundaries of the classes described above in the frequency distribution analysis, and are stored and held in advance by the storage unit 153 (described later) of the printing apparatus 100.

[0064] When analyzing the frequency distribution, the printing control unit 152 calculates the number of printing sites belonging to each of the upper limit side warning area, the lower limit side warning area, the upper limit side NG area, and the lower limit side NG area (the total value of the frequencies belonging to each area). Instead of the total value of the frequencies on the substrate 2 as the analysis unit, the average value of the frequencies for each substrate 2 on the substrate 2 as the analysis unit may be calculated.

[0065] Furthermore, the print control unit 152 may determine that the amount of solder is excessive if the number of printed areas belonging to the upper limit warning area and the upper limit NG area is greater than the number of printed areas belonging to the lower limit warning area and the lower limit NG area. On the other hand, if the number of printed areas belonging to the lower limit warning area and the lower limit NG area is greater than the number of printed areas belonging to the upper limit warning area and the upper limit NG area, the print control unit 152 may determine that the amount of solder is insufficient. If the amount of solder is excessive, the print control unit 152 may change the value of the print parameter to reduce the amount of solder. If the amount of solder is insufficient, the print control unit 152 may change the value of the print parameter to increase the amount of solder.

[0066] This embodiment primarily illustrates the calculation of the number of printed areas belonging to each of the upper limit warning area, lower limit warning area, upper limit NG area, and lower limit NG area, but is not limited to this. For example, the system may be configured to calculate the ratio of the number of printed areas belonging to each of the upper limit warning area, lower limit warning area, upper limit NG area, and lower limit NG area.

[0067] [Regarding the functional configuration of electronic component mounting systems] The functional configuration of the electronic component mounting system 1 will be described with reference to Figure 5. Figure 5 is a block diagram showing an example of the functional configuration of the electronic component mounting system 1.

[0068] The electronic component mounting system 1 includes a printing device 100, a print inspection device 200, and a management device 300 connected to the printing device 100 and the print inspection device 200 via a communication network NT. Note that the work conveyor M3 and mounting devices M4 and M5 are not shown in Figure 4.

[0069] The printing device 100 includes a communication unit 151, a printing control unit 152, a storage unit 153, a substrate holding table moving mechanism 5, a print head 14, a print head moving mechanism 15, a squeegee lifting mechanism 17, and the like. The printing device 100 also includes a display unit 154, a speaker 155, and an operation unit 156.

[0070] The communication unit 151 is connected to the communication network NT outside the printing device 100, and to the print control unit 152 and the storage unit 153, etc., inside the printing device 100. The communication unit 151 communicates various types of data and information.

[0071] The printing control unit 152 oversees various processes performed by each part of the printing apparatus 100 and is connected to, for example, the substrate holding table moving mechanism 5, the print head 14, the print head moving mechanism 15, and the squeegee lifting mechanism 17, and controls these mechanisms.

[0072] The storage unit 153 stores various data and information, such as the aforementioned printing parameter data 153a. The printing parameters are data (specifications) related to the printing parameters of the printing device 100, and include the printing pressure and printing speed related to the squeegee 16, and the plate release speed related to the substrate holding table moving mechanism 5, etc. For example, it may store data such as the initial value, upper limit, lower limit, and the amount of change per value (e.g., 5N) of the printing pressure parameter, which are used when changing the value of the printing pressure parameter. The storage unit 153 may also store the aforementioned thresholds TH11, TH12, TH21, and TH22 that identify areas in the frequency distribution. The storage unit 153 may also store inspection result data obtained from the printing inspection device 200.

[0073] Furthermore, the memory unit 153 also stores tolerance values ​​(see below) to determine whether the inspection results transmitted from the print inspection device 200 are within the acceptable range. Tolerance values ​​may be prepared, for example, for each area used in frequency distribution analysis. Tolerance values ​​are compared, for example, with the number of printed parts belonging to each area (frequency for each area). Tolerance values ​​may differ, for example, between NG areas and warning areas, with the tolerance value for NG areas being smaller than that for warning areas. In other words, it may be acceptable for a certain number of printed parts belonging to the warning area to be included, but not for a number of printed parts belonging to the NG area to be included. Alternatively, the tolerance values ​​may be the same for both NG areas and warning areas. For example, if the tolerance value is set to 0 for both NG areas and warning areas, it is not acceptable for inspection results to belong to either the NG area or the warning area, and it is possible to adjust so that the volume ratio of all printed parts falls within the range of the OK area.

[0074] The printing control unit 152 performs frequency distribution analysis on multiple substrates 2 that are transported continuously, treating each substrate as a single analysis unit, based on the inspection result data from the printing inspection device 200. In the frequency distribution analysis, the printing control unit 152 calculates the number (frequency) of printed areas belonging to the OK area, warning area, and NG area, respectively, based on the frequency distribution table showing the frequency distribution.

[0075] The printing control unit 152 controls each part of the printing apparatus 100 based on multiple printing parameters to perform screen printing on the substrate 2 to be worked on via the screen mask 13. The printing control unit 152 also receives the inspection results from the printing inspection apparatus 200 via the communication unit 151. The printing control unit 152 then performs a frequency distribution analysis based on the inspection results from the printing inspection apparatus 200. Based on the frequency distribution analysis, the printing control unit 152 sequentially selects one of the multiple printing parameters and changes the value of the printing parameter to control (adjust) so that the optimal solder SR is printed on each printing area of ​​the substrate 2 (see below).

[0076] The display unit 154 is a monitor such as an LCD panel, and displays various screens such as the input screen for operation input to the printing device 100. The display unit 154 may display various data and information, for example, information such as printing parameters or inspection results of the printing inspection device 200, or warning information based on frequency distribution analysis.

[0077] Speaker 155 outputs various sounds and voices, such as printing parameters, inspection results from the printing inspection device 200, or information based on the inspection results, in voice. Speaker 155 may also output warning information based on frequency distribution analysis. Various displays and voice outputs may be confirmed by the operator or worker.

[0078] The control unit 156 consists of keys, buttons, or a touch panel, and accepts various operations. These operations may be performed by an operator or worker.

[0079] The print inspection device 200 includes a communication unit 251, an inspection control unit 252, an inspection execution unit 253, and a storage unit 254.

[0080] The communication unit 251 is connected to the communication network NT outside the print inspection device 200, and inside the print inspection device 200, it is connected to the inspection control unit 252, the inspection execution unit 253, and the storage unit 254, etc. The communication unit 251 communicates various types of data and information.

[0081] The inspection control unit 252 coordinates various processes performed by each part of the printing inspection device 200, and for example, controls the inspection execution unit 253. The inspection control unit 252 may, for example, acquire Gerber data 353a (see below), board data 353b, and mounting data 353c held by the management device 300 via the communication unit 251, and store the acquired data in the storage unit 254.

[0082] Gerber data 353a is data that defines the shape and arrangement of pattern holes 13h in the screen mask 13. Gerber data 353a may include information about each of the pattern holes 13h in the screen mask 13. Information about each of the pattern holes 13h in the screen mask 13 may include the position of each pattern hole 13h in the screen mask 13, the height of each pattern hole 13h, the planar area and hole size (volume) of each pattern hole 13h, the shape of each pattern hole 13h, the number of pattern holes 13h, and other information about the pattern holes 13h.

[0083] The substrate data 353b is data relating to the shape of the substrate 2, specifically data defining the shape and arrangement of the electrode pattern, resist, and silk screen on the electrode formation surface. The mounting data 353c is data related to the mounting operation, such as the position coordinates of the component mounting points on the substrate 2.

[0084] The memory unit 254 stores various data and information, for example, it stores inspection data 254a related to inspections.

[0085] The inspection data 254a includes the illumination conditions during imaging in the inspection execution unit 253, the judgment thresholds applied to the pass / fail determination, and the thresholds TH11, TH12, TH21, TH22, etc., from the frequency distribution analysis described above. The inspection data 254a may also include Gerber data 353a, substrate data 353b, and mounting data 353c acquired from the management device 300.

[0086] The inspection execution unit 253 performs a print inspection on the substrate 2 to be worked on, based on the inspection data 254a, in accordance with the control of the inspection control unit 252. In this case, the inspection execution unit 253 may perform the print inspection based on at least one of the Gerber data 353a, substrate data 353b, and mounting data 353c. In the print inspection, the inspection execution unit 253 inspects the printing state of the solder SR printed on all electrodes through all pattern holes 13h of the screen mask 13.

[0087] In print inspection, the inspection execution unit 253 uses a camera to image the substrate 2 after printing has been performed by the printing device 100, and performs recognition processing on the image acquired by the image to inspect the printing state, for example, the volume ratio or area ratio of each printed area.

[0088] For example, as a volume ratio inspection, the inspection unit 253 derives the amount of solder (e.g., volume or area) of the solder SR printed in each of the pattern holes 13h. In this case, the inspection unit 253 may integrate the two-dimensional data of the printed solder SR as described above, or measure the three-dimensional data of the solder SR using a three-dimensional measuring instrument. By doing so, the inspection unit 253 may derive the volume or area of ​​the solder SR printed in each printed area. Alternatively, the inspection unit 253 may calculate the volume ratio or area ratio of the solder SR printed in each printed area based on each of the hole sizes included in the Gerber data 353a and the derived amount of solder SR.

[0089] The management device 300 includes a communication unit 351, a management control unit 352, a storage unit 353, and a display unit 355.

[0090] The communication unit 351 is connected to the printing device 100 and the print inspection device 200 via the communication network NT outside the management device 300, and communicates with each of these devices. The communication unit 351 transmits various data and information. For example, the communication unit 351 receives data of the print inspection results from the print inspection device 200. The communication unit 351 is also connected to the management control unit 352, the storage unit 353, and the display unit 355 inside the management device 300.

[0091] The display unit 355 is a monitor such as an LCD panel and displays various screens, such as the input screen for operation input to the management device 300. The display unit 355 of the management device 300 displays various data and information. The storage unit 353 of the management device 300 stores various data and information, such as Gerber data 353a, board data 353b, and mounting data 353c.

[0092] The management control unit 352 oversees various processes performed by the management device 300. The management control unit 352 can, for example, transmit Gerber data 353a, board data 353b, and mounting data 353c to other devices (e.g., the printing inspection device 200) via the communication unit 351. The management control unit 352 can, for example, transmit inspection result data from the printing inspection device 200 to the printing device 100 via the communication unit 351 of the management device 300.

[0093] The various control units (for example, the printing control unit 152, the inspection control unit 252, and the management control unit 352) are composed of a processor. The processor includes, for example, an MPU (Micro Processing Unit), a CPU (Central Processing Unit), or a DSP (Digital Signal Processor). The various control units perform various processes or controls by executing programs held in various storage units (for example, storage unit 153, storage unit 254, and storage unit 353). The various storage units include, for example, RAM (Random Access Memory) or ROM (Read Only Memory). The various storage units may also include HDD (Hard Disk Drive) or SSD (Solid State Drive). The various storage units may also include optical discs or SD cards. The various storage units store and hold, for example, various data, various information, or various programs.

[0094] [About the operation flow in the print control unit] The operation flow performed by the print control unit 152 of the printing device 100 will be explained with reference to Figures 6 and 7. Figure 6 is a flowchart showing an example of the operation flow performed by the print control unit 152 shown in Figure 5. Figure 7 is a flowchart showing an example of the operation flow of subroutines SR10 and SR20 shown in Figure 6. Since subroutines SR10 and SR20, which will be described later, have the same operation flow, the explanation of subroutine SR20 will be omitted in the following explanation.

[0095] The print control unit 152 sequentially acquires (receives) inspection result data from the print inspection device 200 via the management control unit 352 and the communication unit 151 (S11).

[0096] The print control unit 152 performs a frequency distribution analysis based on the acquired inspection results and sequentially derives the number of printed areas belonging to the OK area, upper limit warning area, lower limit warning area, upper limit NG area, and lower limit NG area. The print control unit 152 compares and determines whether each of the acquired inspection results is within the range of the tolerance value, based on the tolerance value that is set in advance and stored in the storage unit 153 (S12).

[0097] For example, the print control unit 152 may determine that the print area is within the acceptable range if the number of print areas belonging to the upper limit NG area is less than or equal to the allowable value (allowable number) of the upper limit NG area. The print control unit 152 may determine that the print area is within the acceptable range if the number of print areas belonging to the upper limit warning area is less than or equal to the allowable value (allowable number) of the upper limit warning area. The print control unit 152 may determine that the print area is within the acceptable range if the number of print areas belonging to the lower limit NG area is less than or equal to the allowable value (allowable number) of the lower limit NG area. The print control unit 152 may determine that the print area is within the acceptable range if the number of print areas belonging to the lower limit warning area is less than or equal to the allowable value (allowable number) of the lower limit warning area. The print control unit 152 may also determine whether the print area is within the acceptable range by combining the results of comparison with the allowable values ​​in each of these areas. For example, if the print control unit 152 determines that the print area as a whole is not within the acceptable range if it determines that at least one of these areas (for example, the four areas mentioned above) is not within the acceptable range, it may determine that the entire area is not within the acceptable range. On the other hand, if the print control unit 152 determines that all of these areas (for example, the four areas mentioned above) are not within the acceptable range, it may determine that the area as a whole is within the acceptable range.

[0098] If the comparison judgment in step S12 determines that the entire area is within the acceptable range (YES in step S12), the operation flow returns to step S11.

[0099] On the other hand, if it is determined that the entire area is not within the acceptable range, that is, outside the acceptable range (NO in step S12), the print control unit 152 executes a subroutine related to the process of changing the print parameters (subroutine SR10).

[0100] As shown in Figure 7, in subroutine SR10, the print control unit 152 checks the currently selected print parameter from among several print parameters (e.g., printing pressure, printing speed, or stencil release speed) (S21). The print control unit 152 determines whether changing the value of the selected print parameter would exceed the upper or lower limit (upper or lower limit) (S22). If the result of this determination is that the upper or lower limit is not exceeded (NO in step S22), the print control unit 152 determines whether the sign of the inspection result has been reversed (S24). If the result is that the sign has not been reversed (NO in step S24), the print control unit 152 adjusts the value of the currently selected print parameter (S25).

[0101] The test results will be evaluated as follows: For example, the printing control unit 152 obtains the volume percentage of the printed solder for each inspection point and assigns a score of +1 (warning) if it exceeds the threshold TH11. The printing control unit 152 assigns a score of +2 (abnormal) if the obtained volume percentage of solder exceeds the threshold TH21. Similarly, the printing control unit 152 assigns a score of -1 (warning) if the obtained volume percentage of solder falls below the threshold TH12, and a score of -2 (abnormal) if it falls below the threshold TH22. The printing control unit 152 determines that there is an excess of solder if the total score for all inspection points is "+", i.e., a positive value. Conversely, it determines that there is an insufficient amount of solder if the total score is "-", i.e., a negative value.

[0102] Print parameters can be adjusted as follows: For example, if the total score of the inspection points is +5 before changing the print parameters and becomes -3 after changing the print parameters, the print control unit 152 will determine that the print result has improved because it is approaching normal (±0). However, since the sign has reversed, it is expected that further changes to the same print parameters will only increase the negative value, and therefore it is considered that further changes to the print parameters will not improve the print result. Accordingly, the print control unit 152 will terminate the change to the print parameter at the point when the sign of the total score reverses and proceed to change the next print parameter. In this way, the reversal of the sign of the inspection result is used as a criterion for switching the print parameter being adjusted to a different print parameter. Furthermore, if the inspection result score before the change was +5 and the inspection result score after the change becomes -8, the print control unit 152 will consider it to have worsened and will cancel the change to that print parameter itself.

[0103] In step S22, if it is determined that changing the value of the selected print parameter would exceed the upper or lower limit (YES in step S22), the print control unit 152 selects a print parameter different from the currently selected print parameter (S23) and adjusts the value of that print parameter (S25).

[0104] In step S24, if the code of the inspection result is determined (YES in step S24), the print control unit 152 selects a print parameter different from the currently selected print parameter (S23) and adjusts the value of that print parameter (S25). For example, when the print parameter is changed in steps S22 and S24, the value of the changed print parameter is set to the initial value.

[0105] Returning to Figure 6, the print control unit 152 executes subroutine SR10 and then acquires the inspection result data of the print inspection by the print inspection device 200 again via the management control unit 352 and the communication unit 151 (S13). In this print inspection, the substrate 2 printed using the print parameters adjusted by subroutine SR10 is inspected. Based on the inspection results acquired again, the print control unit 152 performs frequency distribution analysis again and compares and determines whether the inspection results are within the acceptable range for the entire area (S14). If the comparison determination determines that it is within the acceptable range (YES in step S14), the print control unit 152 changes the print parameter to the printing pressure of the squeegee 16 and adjusts its magnitude (S15). In other words, as the initial setting of the print parameters, the print control unit 152 selects printing pressure as the print parameter and sets its initial value. After adjusting the print parameters, the operation flow returns to step S11.

[0106] In step S15, if the print control unit 152 determines, based on the comparison judgment in step S14, that the acquired inspection results fall within the acceptable range for the entire area, it may maintain the print parameter settings that have fallen within the acceptable range, rather than resetting (changing) the print parameters to their initial settings.

[0107] On the other hand, in step S14, if it is determined that the inspection result is not within the acceptable range for the entire area (NO in step S14), the print control unit 152 determines, based on the history of past inspection results, whether the current inspection result obtained in step S13 has improved compared to the inspection result obtained in the past (for example, the one immediately preceding the current one). In this case, for example, it determines whether the total number of printed parts belonging to the warning area and NG area has decreased in the current inspection result compared to the past inspection result (S16). If it is determined that there has been improvement (YES in step S16), the operation flow returns to step S13.

[0108] On the other hand, if it is determined that the inspection results have not improved (NO in step S16), the print control unit 152 cancels (undoes) the current change or adjustment of the print parameters (change or adjustment of the print parameters in the previous subroutine SR10 or subroutine SR20) (S17). In other words, the print control unit 152 compares the volume ratio or area ratio included in the current inspection result with the volume ratio included in the previous inspection result immediately preceding it, and if the current volume ratio is worse than the previous one, it resets the print parameters to their original state. After processing in step S17, the print control unit 152 executes subroutine SR20. After the execution of subroutine SR20, the operation flow returns to step S13. As mentioned above, the operation flow in subroutine SR20 is the same as that of subroutine SR10.

[0109] Next, referring to Figure 8, the procedure for changing and adjusting print parameters (steps S23, S25) in subroutine SR10 (and similarly for SR20) and its technical significance will be explained. Figure 8 shows an example of the procedure by which the print control unit 152 changes print parameters.

[0110] When changing and adjusting multiple printing parameters, the printing control unit 152 first selects and changes the printing pressure as the first option (first candidate) of the printing parameters, and then adjusts the magnitude of that printing pressure. For example, the printing control unit 152 sets the initial value of the printing pressure to 40N and attempts to improve the printing condition by decreasing the printing pressure by 5N for each change (adjustment).

[0111] Next, if changing the printing pressure does not increase or decrease the number of items belonging to the warning area and NG area in the frequency distribution analysis (i.e., the printing condition does not improve), the print control unit 152 selects and changes the printing speed as the second option (second candidate) and adjusts the magnitude of that printing speed. Furthermore, if changing the magnitude of that printing speed does not improve the printing condition, the print control unit 152 selects and changes the stencil release speed as the third option (third candidate) and adjusts the magnitude of that stencil release speed.

[0112] In other words, when the print control unit 152 changes the print parameters based on the inspection results from the print inspection device 200, it selects the print parameters to be changed in the order of printing pressure, printing speed, and stencil release speed, and adjusts their magnitudes. Regarding the degree to which changes in print parameters affect the amount of solder SR (volume ratio or area ratio) in each printed area, printing pressure has the greatest impact, followed by printing speed, and then stencil release speed. Therefore, the print control unit 152 selects and changes the print parameters in the order described above.

[0113] Furthermore, for example, if the print control unit 152 determines that the volume ratio is high if the number of items in the upper limit warning area and the upper limit NG area exceeds the allowable value based on the frequency distribution analysis, it will sequentially reduce the printing pressure to decrease the amount of solder SR in the pattern holes 13h. If no improvement is seen even after this, specifically if the number of items in the upper limit warning area and the upper limit NG area still exceeds the allowable value even when using the printing pressure that has reached the lower limit after the change, the print control unit 152 will then sequentially increase (speed up) the printing speed to decrease the amount of solder SR in the pattern holes 13h.

[0114] For example, if the number of items in the lower limit warning area and the lower limit NG area exceeds the allowable value for volume ratio, the print control unit 152 determines that the volume ratio is low and operates to gradually increase the printing pressure and increase the amount of solder SR in the pattern holes 13h. Furthermore, if no improvement is seen even after this, specifically if the number of items in the lower limit warning area and the lower limit NG area still exceeds the allowable value even when using the printing pressure that has reached the upper limit after the change, the print control unit 152 then operates to gradually decrease (slow down) the printing speed and increase the amount of solder SR in the pattern holes 13h.

[0115] Furthermore, regarding the printing parameter of the plate release speed, it is often difficult to definitively determine the causal relationship between the plate release speed and the increase or decrease in the volume ratio of solder SR. For this reason, the printing control unit 152 may, for example, first adjust the plate release speed to gradually increase (become faster). Then, if no improvement in the volume ratio is observed even after increasing the plate release speed to its upper limit, the printing control unit 152 may then adjust the plate release speed to gradually decrease (become slower).

[0116] Furthermore, among the multiple printing parameters, the printing parameters used to optimize the amount of solder filled into the printed area of ​​the substrate 2 may be at least two (or more) of the printing pressure, printing speed, and stencil release speed. Even in this case, the printing apparatus 100 can suppress the occurrence of printing defects by adaptively selecting and adjusting the printing parameters.

[0117] In this way, the printing apparatus 100 adaptively changes and adjusts multiple printing parameters based on the inspection results of the printing inspection apparatus 200 to optimize the amount of solder in each printed area of ​​the substrate 2. As a result, the printing apparatus 100 can adaptively change the printing parameters based on the current printing state, such as the state of the solder SR or screen mask 13, and adjust the magnitude of these printing parameters to suppress the occurrence of printing defects.

[0118] [Regarding the first specific example] A first specific example according to the first embodiment will be described with reference to Figure 9. Figure 9 is a diagram illustrating a first specific example showing how the inspection result of the solder amount changes with changes and adjustments to the printing parameters. In Figure 9, it is illustrated that the inspection result converges within the OK area when the printing pressure and printing speed are changed as printing parameters.

[0119] Figure 9 shows how the results of the frequency distribution analysis change over time, as data acquisition and frequency distribution analysis of inspection results are performed multiple times while changing the printing parameters. The same applies to Figure 10. Furthermore, Figures 9 and 10 illustrate that the tolerance values ​​for the upper limit warning area, lower limit warning area, upper limit NG area, and lower limit NG area are all 0. In other words, it illustrates that the printing parameters are repeatedly adjusted until the number of printed areas belonging to the upper limit warning area, lower limit warning area, upper limit NG area, and lower limit NG area becomes 0.

[0120] The print control unit 152 acquires data from the print inspection device 200 (see step S11 in Figure 6). Based on the inspection results, the print control unit 152 appropriately compares and determines whether the number of printed areas belonging to the OK area, upper limit warning area, lower limit warning area, upper limit NG area, and lower limit NG area is within the allowable range (see step S12 in Figure 6).

[0121] First, in state A, the number of NG areas on the upper limit and the number of printed areas belonging to the NG areas on the upper limit are greater than or equal to the allowable value and are determined to be outside the allowable range. In other words, the printing state is one in which there is too much solder, so the printing control unit 152 primarily selects the printing pressure from among several printing parameters (first candidate) and adjusts it by reducing (lowering) the printing pressure (see subroutine SR10 in Figure 6).

[0122] After adjusting the printing pressure to be lower, the printing control unit 152 acquires the inspection result data from the printing inspection device 200 again, similarly recalculates the number of printed areas belonging to each area, and compares and determines whether or not it is within the acceptable range (see steps S13 and S14 in Figure 6).

[0123] By reducing the printing pressure, for example, the number of printed areas belonging to the upper limit NG area decreases, which improves the inspection result, but the condition of being outside the acceptable range may continue. In this case, the printing control unit 152 sequentially reduces the printing pressure until it reaches the lower limit. That is, steps S14, S16 in Figures 6 and 7, steps S21, S22, S25 of subroutine SR20, etc. are repeatedly executed.

[0124] In state B, based on the inspection results data when the printing pressure is at the lower limit, there are no inspection results belonging to the upper limit NG area, but there are still inspection results belonging to the upper limit warning area, and it is determined that the values ​​are outside the acceptable range. In this case, reducing the printing pressure will bring it below the lower limit of the printing pressure, so the next printing parameter is selected as the printing speed, and the printing speed is set (adjusted) to the initial value (steps S13, S14, S16 in Figures 6 and 7, and steps S21, S22, S23, S25 in subroutine SR20).

[0125] The print control unit 152 acquires the inspection result data from the print inspection device 200 again. Even if the print parameter is changed to the initial value of the print speed, the print control unit 152 finds that the inspection result is still in the upper limit warning area, and although the print condition has improved, it is still outside the acceptable range. In this case, the print condition still has an excessive amount of solder, so, as with the printing pressure, the print control unit 152 adjusts by increasing (speeding up) the print speed (steps S13, S14, S16, subroutine SR10 in Figure 6).

[0126] After adjusting the printing speed to be increased, the print control unit 152 acquires the inspection result data from the print inspection device 200 again, similarly recalculates the number of printed parts belonging to each area, and compares and determines whether or not it is within the acceptable range (see steps S13 and S14 in Figure 6).

[0127] Increasing the printing speed improves the inspection results, for example, by reducing the number of printed areas belonging to the upper limit warning area, but the condition of being outside the acceptable range may continue. In this case, the printing control unit 152 sequentially increases the printing speed until it reaches the upper limit. That is, steps S14, S16 in Figures 6 and 7, steps S21, S22, S25 of subroutine SR20, etc. are repeatedly executed.

[0128] In state C, based on the inspection results data from the print inspection when the print speed is at its upper limit, the inspection results remaining belong to the upper limit warning area and are determined to be outside the acceptable range. In this case, increasing the print speed will result in a print speed below the upper limit, so the next print parameter selected is the stencil release speed, and the stencil release speed is set (adjusted) to its initial value (steps S13, S14, S16 in Figures 6 and 7, and steps S21, S22, S23, S25 in subroutine SR20).

[0129] The print control unit 152 acquires the inspection result data from the print inspection device 200 again. Even after changing the print parameter to the initial value of the stencil release speed, the print control unit 152 finds that the inspection result still falls within the upper limit warning area, indicating that although the print condition has improved, it is still outside the acceptable range. In this case, since the amount of solder is still excessive, the print control unit 152 adjusts the stencil release speed by increasing (decreasing) it (steps S13, S14, S16 in Figure 6, subroutine SR10).

[0130] After adjusting the plate release speed to be larger, the printing control unit 152 acquires the inspection result data from the printing inspection device 200 again, similarly recalculates the number of printed parts belonging to each area, and compares and determines whether each of these numbers is within the acceptable range (see steps S13 and S14 in Figure 6).

[0131] Increasing the stencil release speed improves the inspection results, for example, by reducing the number of printed areas belonging to the upper limit warning area, but the condition of being outside the acceptable range may continue. In this case, the print control unit 152 sequentially increases the stencil release speed until it reaches the upper limit. That is, steps S14, S16 in Figures 6 and 7, steps S21, S22, S25 of subroutine SR20, etc. are repeatedly executed.

[0132] In state D, before the stencil release speed reaches the upper limit, there are no inspection results belonging to the upper limit warning area, and it is determined that the result is within the acceptable range. In other words, all non-OK areas—the upper limit OK area, the upper limit warning area, the lower limit OK area, and the lower limit warning area—are within the acceptable range. Therefore, the electronic component mounting system 1 can appropriately adjust the amount of solder for each printed area by sequentially changing the printing parameters, thereby suppressing the occurrence of printing defects.

[0133] [Regarding the second specific example] A second specific example according to the first embodiment will be described with reference to Figure 10. Figure 10 is a diagram illustrating a second specific example showing how the inspection results of the solder amount change with changes in printing parameters. In Figure 10, it is shown that adjusting the printing pressure as a printing parameter did not improve the printing condition.

[0134] State A2 is the same as State A. In other words, the number of printed areas in the upper limit NG area and the number of printed areas belonging to the upper limit NG area are above the allowable value, so it is determined that it is outside the allowable range. In other words, it is a printing state with an excessive amount of solder, so the printing control unit 152 primarily selects the printing pressure from among several printing parameters (first candidate) and adjusts it by reducing (lowering) the printing pressure (see subroutine SR10 in Figure 6).

[0135] After adjusting the printing pressure by reducing it once or more, the printing control unit 152 acquires the inspection result data from the printing inspection device 200 again, similarly recalculates the number of printed parts belonging to each area, and compares and determines whether each of these numbers is within the acceptable range (see steps S13 and S14 in Figure 6).

[0136] As a result of adjusting the printing pressure by reducing it once or more, as in state B2, the number of printed areas belonging to the lower limit NG area and the lower limit NG area is greater than or equal to the allowable value, and is therefore determined to be outside the allowable range. In this case, the printing control unit 152 compares the total number of printed areas in the upper limit NG area and the upper limit NG area at state A2 with the total number of printed areas in the lower limit NG area and the lower limit NG area at state B2. At this time, the printing control unit 152 determines that the total number at state B2 is greater than the total number at state A2, and that the inspection result has not improved (No. in step S16 of Figure 6). In this case, the previous change in printing parameters (e.g., reduction in printing pressure) is canceled (step S17 of Figure 6). As a result, printing is performed with the previous printing parameters canceled, and the printing state becomes state C2, which is equivalent to returning to state A2. Then, in subroutine SR20, since the sign of the inspection result has been reversed, the print control unit 152 changes the print parameter to the next print parameter (for example, print speed) and sets it to the initial value of the print speed (steps S24, S23, S25 of subroutine SR20 in Figure 7). Then, the print control unit 152 sequentially increases the print speed as needed.

[0137] In state D2, before the printing speed reaches its upper limit, the volume ratio included in the inspection result is such that there are no printed areas belonging to the upper limit NG area and upper limit warning area, and it is determined that it is within the acceptable range. In other words, all non-OK areas, namely the upper limit OK area, upper limit warning area, lower limit OK area, and lower limit warning area, are within the acceptable range. Therefore, the electronic component mounting system 1 can appropriately adjust the amount of solder for each printed area by sequentially changing the printing parameters, thereby suppressing the occurrence of printing defects.

[0138] In this manner, the printing apparatus 100 of this embodiment acquires the inspection results of printing on the substrate 2 and counts the number of warnings (number of printed areas belonging to the warning area) and the number of NGs (number of printed areas belonging to the NG area) for the amount of solder printed on the printed area. In other words, the printing apparatus 100 can improve the first-pass yield and reduce the overall line stoppage rate by adjusting the printing parameters based on the frequency distribution analysis.

[0139] Furthermore, the printing device 100 adjusts (changes) only one printing parameter at a time, sequentially switching the parameter being adjusted: after changing the printing pressure, it adjusts the printing speed, then the stencil release speed, and so on. This allows the printing device 100 to determine which printing parameter adjustment was effective. Based on frequency distribution analysis, if the printing quality deteriorates with the changed printing parameters or values, the printing device 100 can revert to the previous printing parameters or values.

[0140] In this embodiment, the upper and lower limits of the print parameter values, or the amount of change per change, etc., may be predetermined as fixed values, or they may be dynamically changed by an operator or worker via the control unit 156, for example.

[0141] Furthermore, although this embodiment illustrates that the order of changing the printing parameters is printing pressure, printing speed, and stencil release speed, other orders are also possible. In addition, the printing parameters may include parameters other than these three parameters (for example, the attack angle of the squeegee 16).

[0142] Furthermore, in this embodiment, if the printing condition does not improve and the printing parameters are to be restored to their original state, the printing control unit 152 of the printing device 100 may restore the predetermined printing parameters to their original values ​​if the printing condition does not improve after adjusting the values ​​of the predetermined printing parameters. Also, if the printing condition does not improve after changing from a predetermined printing parameter (e.g., printing pressure) to another printing parameter (e.g., printing speed), the printing control unit 152 may restore the printing parameter to its original value (e.g., printing pressure), and then change to yet another printing parameter (e.g., stencil release speed).

[0143] [Summary of the first embodiment] As described above, the electronic component mounting system 1 (an example of a printing system) of this embodiment prints solder SR onto multiple substrates 2. The electronic component mounting system 1 includes a printing device 100 that uses a squeegee 16 to print solder SR onto electrodes formed on each of the multiple substrates 2 via a screen mask 13 (an example of a mask) having predetermined pattern holes 13h (an example of an opening). The electronic component mounting system 1 includes a printing inspection device 200 (an example of an inspection device) that inspects the amount of first solder printed on the first substrate among the multiple substrates 2 and transmits the first inspection result to the printing device 100. Based on the first inspection result, the printing device 100 changes the first printing parameter among a plurality of printing parameters and prints solder SR on the second substrate that is transported after the first substrate. The printing inspection device 200 inspects the amount of second solder printed on the second substrate and transmits the second inspection result to the printing device 100. Based on the second inspection result, the printing device 100 changes a second printing parameter, which is different from the first printing parameter, among a plurality of printing parameters.

[0144] The printing apparatus 100 of this embodiment is located upstream of a printing inspection apparatus 200 that prints solder SR onto multiple substrates 2 and inspects the printed solder SR. The printing apparatus 100 includes a printing head 14 (an example of a printing unit) that prints solder SR onto electrodes formed on each of the multiple substrates 2 using a squeegee 16 via a screen mask 13 having predetermined pattern holes 13h. The printing apparatus 100 includes a communication unit 151 that receives the inspection result of a first solder amount printed on a first substrate among the multiple substrates 2 from the printing inspection apparatus 200. The printing apparatus 100 includes a printing control unit 152 (an example of a control unit) that changes a first printing parameter among multiple printing parameters based on the inspection result of the first solder amount. The printing head 14 prints solder SR on a second substrate that is transported after the first substrate using the first printing parameter. The communication unit 151 receives the inspection result of a second solder amount printed on a second substrate among the multiple substrates 2 from the printing inspection apparatus 200. The printing control unit 152 changes a second printing parameter, which is different from the first printing parameter, among a plurality of printing parameters, based on the inspection result of the solder amount of the second substrate.

[0145] As a result, the electronic component mounting system 1 and the printing apparatus 100 adaptively change and adjust one of several printing parameters (an example of a second printing parameter) that is different from one printing parameter (an example of a first printing parameter) based on the inspection results from the printing inspection apparatus 200. As a result, the electronic component mounting system 1 and the printing apparatus 100 adaptively change the printing parameters taking into account the current printing state based on the state of the solder SR or screen mask 13, and by adjusting the degree of the changed printing parameters, they control the system to optimize the amount of solder at each printed area (corresponding to the area where electrodes are formed) on the substrate 2, thereby suppressing the occurrence of printing defects.

[0146] Furthermore, the printing device 100 compares the first solder amount with the second solder amount, and if the second solder amount is worse than the first solder amount, it may revert the first printing parameter to its original state. Therefore, if the change to the first printing parameter is deemed inappropriate, the printing device 100 may, instead of changing to the second printing parameter and adjusting its balance, or adjust the second printing parameter and revert to the first printing parameter. This allows the printing device 100 to suppress deterioration of the printing state due to the change to the first printing parameter and to restart solder amount optimization, for example, using a different approach.

[0147] Furthermore, the printing inspection device 200 may obtain the first solder amount and the second solder amount as the area ratio of solder SR printed on the first substrate and the second substrate with respect to a predetermined pattern hole 13h. This allows the printing inspection device 200 to derive the solder amount for each printed area of ​​the substrate 2 in a planar (two-dimensional) manner, and can be easily derived, for example, by processing a planar image.

[0148] Furthermore, the printing inspection device 200 may obtain the first solder quantity and the second solder quantity as the volume fraction of solder SR printed on the first substrate and the second substrate with respect to predetermined pattern holes 13h. This allows the printing inspection device 200 to spatially (three-dimensionally) derive the solder quantity for each printed area of ​​the substrate 2, enabling a more accurate determination of the solder quantity.

[0149] Furthermore, the multiple printing parameters may consist of at least two of the following: printing pressure, printing speed, and stencil release speed. This allows the printing device 100 to sequentially change at least two printing parameters as a first and second printing parameter to optimize the amount of solder and bring the printing state closer to a desirable state.

[0150] While embodiments have been described above with reference to the drawings, it goes without saying that this disclosure is not limited to such examples. It is clear to those skilled in the art that various modifications, alterations, substitutions, additions, deletions, and equivalents can be conceived within the scope of the claims, and these are also understood to fall within the technical scope of this disclosure. Furthermore, the components of the embodiments described above can be combined in any way without departing from the spirit of the invention. [Industrial applicability]

[0151] This disclosure is useful as a printing system, printing apparatus, and printing method that can determine printing conditions by taking into account the current printing state based on the condition of the solder or mask, and can suppress the occurrence of printing defects. [Explanation of Symbols]

[0152] 1. Electronic component mounting system 2 circuit boards 4. Circuit board holding table 5. Substrate holding table moving mechanism 6. Substrate transport mechanism 13 Screen Masks 13a Mask frame 13c Bottom side 13h pattern holes 13h1 Small Pattern Hole 13h2 Large Pattern Hole 14 Printhead 15 Print head movement mechanism 16 squeegee 17. Squeegee Lifting Mechanism 100 Printing device 151 Communications Department 152 Printing Control Unit 153 Storage section 153a Print Parameter Data 154 Display section 155 speakers 156 Operation section 200 Printing Inspection Devices 251 Communications Department 252 Inspection Control Unit 253 Inspection Execution Department 254 Storage section 254a Inspection data 300 Management device 351 Communications Department 352 Management and Control Unit 353 Storage section 353a Gerber data 353b PCB data 353c Implementation Data 355 Display section M3 Work Conveyor M4 mounting device M5 mounting device NT communication network SR Handa θ Rotation direction

Claims

1. A printing system for printing solder onto multiple circuit boards, A printing apparatus that prints solder onto electrodes formed on each of the plurality of substrates using a squeegee through a mask having a predetermined opening, An inspection device that inspects the amount of solder printed on the first substrate among the plurality of substrates and transmits the first inspection result to the printing device, Equipped with, The printing apparatus modifies the first printing parameter among a plurality of printing parameters based on the first inspection result, and prints the solder onto the second substrate that was transported after the first substrate. The inspection device inspects the amount of second solder printed on the second substrate and transmits the second inspection result to the printing device. If the second inspection result is not improved compared to the first inspection result, the printing apparatus cancels the change to the first printing parameter and changes a second printing parameter that is different from the first printing parameter among the multiple printing parameters. Printing system.

2. The printing apparatus compares the first solder quantity with the second solder quantity, and if the second solder quantity is worse than the first solder quantity, it restores the first printing parameter to its original state. The printing system according to claim 1.

3. The inspection device obtains the first solder quantity and the second solder quantity as area ratios of the solder printed on the first substrate and the second substrate with respect to the predetermined opening. The printing system according to claim 1 or 2.

4. The inspection device obtains the first solder quantity and the second solder quantity as volume ratios of the solder printed on the first substrate and the second substrate with respect to the predetermined opening. The printing system according to claim 1 or 2.

5. The aforementioned multiple printing parameters are at least two of the following: printing pressure, printing speed, and ink release speed. The printing system according to claim 1 or 2.

6. A printing device installed upstream of an inspection device that prints solder onto multiple circuit boards and inspects the printed solder, A printing unit that prints the solder onto electrodes formed on each of the plurality of substrates using a squeegee through a mask having a predetermined opening, A communication unit receives a first inspection result from the inspection device, in which the amount of solder printed on the first substrate among the plurality of substrates is inspected. A control unit that changes a first print parameter among a plurality of print parameters based on the first inspection result, Equipped with, The printing unit prints the solder onto the second substrate, which is transported after the first substrate, using the first printing parameters. The communication unit receives a second inspection result from the inspection device, which is an inspection result of the amount of second solder printed on the second substrate among the plurality of substrates. If the second inspection result is not improved compared to the first inspection result, the control unit cancels the change to the first print parameter and changes a second print parameter that is different from the first print parameter among the multiple print parameters. Printing device.

7. A printing method for printing solder onto multiple circuit boards, The steps include printing the solder onto an electrode formed on a first substrate among the plurality of substrates using a squeegee through a mask having a predetermined opening, The steps include receiving a first inspection result from an inspection device that inspects the printed solder, which indicates that the amount of first solder printed on the first substrate has been inspected, Based on the first inspection result, the first print parameter is changed from among multiple print parameters, The steps include: using the first printing parameters, printing the solder onto electrodes formed on a second substrate transported after the first substrate via the mask using the squeegee; The steps include receiving a second inspection result from the inspection device, in which the amount of second solder printed on the second substrate has been inspected, If the second test result is not an improvement compared to the first test result, the steps include: undoing the change to the first print parameter and changing a second print parameter that is different from the first print parameter among the multiple print parameters; A printing method that includes [something].

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