Screen printing device

Abstract

To manage a coating material on a screen mask more appropriately.SOLUTION: A printing device 1 comprises: a squeegee 16 having a pressing surface 16a; a detection unit that detects a solder roll S on a mask 6; an X-axis drive mechanism 10 for moving the detection unit in an X direction; and a supply control unit 102 that controls the X-axis drive mechanism 10, calculates the X-direction width of the solder roll S on the basis of detection of the solder roll S by the detection unit along with the movement in the X direction, and determines the necessity of supplying solder on the basis of the width. The detection unit includes first and second sensors 44a and 44b each including non-contact sensors and arrayed in a Y direction. The supply control unit 102 calculates the width of the solder roll S at the detection position of each of the sensors 44a and 44b and performs the determination process on the basis of the width.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a screen printing apparatus that prints (applies) a coating material such as cream solder onto a substrate such as a printed circuit board. [Background technology]

[0002] There is known a screen printing apparatus (hereinafter simply referred to as a printing apparatus) that prints a coating material, such as cream solder, onto a substrate such as a printed circuit board through openings (mask openings) in a screen mask (hereinafter simply referred to as a mask) while moving the coating material with a squeegee over the screen mask that is superimposed on the substrate. In this type of printing apparatus, a sensor detects the coating material on the mask after each set number of prints, and supplies (replenishes) the coating material as needed. Specifically, as disclosed in Patent Document 1, a sensor scans the top surface of the mask in the direction of squeegee movement to measure the width of the coating material, and determines whether or not to supply the coating material based on the measurement results, thereby supplying the coating material onto the mask. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-179628 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the conventional printing device disclosed in Patent Document 1, the sensor is fixedly positioned at a predetermined location along the longitudinal direction of the squeegee. In other words, the squeegee width is measured only at one location along the longitudinal direction of the coating material extending along the squeegee on the mask. Therefore, for example, if there is a locally narrow area of ​​the coating material away from the sensor, the supply of the coating material may be delayed, and in the worst case, this may lead to a deterioration in print quality.

[0005] The present invention has been made in view of the above circumstances, and has an object to provide a screen printing apparatus that can more appropriately manage the coating material on the screen mask. [Means for solving the problem]

[0006] In order to solve the above problem, a screen printing apparatus according to one aspect of the present invention comprises: a squeegee having a pressing surface extending in a first direction and moving a coating material along a screen mask via the pressing surface in a second direction perpendicular to the first direction; a detection unit that detects the coating material on the screen mask; a movement mechanism that moves the detection unit in the second direction; and a control unit that controls the movement mechanism and determines the width of the coating material in the second direction based on detection of the coating material by the detection unit as it moves in the second direction, and performs a determination process as to whether or not the coating material needs to be supplied based on the width, wherein the detection unit includes a plurality of sensors each consisting of a non-contact sensor and aligned in the first direction, and the control unit determines the width of the coating material at the detection position of each of the plurality of sensors and performs the determination process based on the width.

[0007] According to this screen printing device, the widths (widths in the second direction) of the coating material on the screen mask pressed by the squeegee, specifically, the mass of coating material arranged on the screen mask so as to extend in the first direction, are determined at a plurality of different positions in the longitudinal direction (first direction) of the coating material, and a determination is made as to whether or not the coating material needs to be supplied based on the determined widths. Therefore, compared to conventional devices that determine whether or not the coating material needs to be supplied by determining the width at only one position on the coating material, the determination as to whether or not the coating material needs to be supplied can be made more accurately, and as a result, the coating material on the screen mask can be more appropriately managed.

[0008] Preferably, when the moving mechanism is defined as a second moving mechanism, the device further comprises a supply unit that moves in the second direction together with the plurality of sensors by the second moving mechanism and is capable of supplying coating material onto the screen mask, and a first moving mechanism that moves the supply unit in the first direction, and the control unit is configured to further control the first moving mechanism and the supply unit, and when it is determined in the necessity determination process that supply of coating material is necessary, identify a shortage of the coating material on the screen mask and move the supply unit in the first direction to supply the coating material to the shortage.

[0009] This configuration allows the coating material to be supplied directly and quickly to a local shortage of coating material extending in the first direction, which is useful for appropriately managing the coating material on the screen mask.

[0010] In this case, the plurality of sensors may be disposed such that their detection positions equally divide the width dimension of the squeegee in the first direction.

[0011] This configuration allows multiple sensors to detect the coating material in a balanced manner (at equal intervals in the first direction) without being affected by the size of the squeegee, which is advantageous for accurately determining whether or not the coating material needs to be supplied.

[0012] Furthermore, in the screen printing apparatus according to the above aspect, when the movement mechanism is defined as a second movement mechanism, the screen printing apparatus may further include a first movement mechanism that moves the plurality of sensors integrally in the first direction, and the control unit may be configured to further control the first movement mechanism.

[0013] According to this configuration, it is possible to cause each of the plurality of sensors to detect the application material at a plurality of mutually different positions in the first direction, and therefore it is possible to obtain the width of the application material in more detail along the longitudinal direction.

[0014] Preferably, the control unit is configured to cause each of the plurality of sensors to detect the coating material at a plurality of different positions in the first direction by alternately performing a scanning operation that moves the plurality of sensors in the second direction to detect the coating material and a sliding operation that moves the plurality of sensors in the first direction.

[0015] According to this configuration, it is possible to cause each of the plurality of sensors to efficiently detect the applying material at a plurality of mutually different positions in the first direction.

[0016] In this case, it is preferable that the system further includes a supply unit that moves in the second direction together with the multiple sensors by the second movement mechanism and is capable of supplying coating material onto the screen mask, and a third movement mechanism that moves the supply unit in the first direction, and that the control unit further controls the third movement mechanism and the supply unit, and when it is determined in the necessity determination process that supply of coating material is necessary, identifies an area where there is a shortage of coating material on the screen mask and moves the supply unit to supply coating material to the area where there is a shortage.

[0017] This configuration allows the coating material to be supplied directly and quickly to a local shortage of coating material extending in the first direction, which is useful for appropriately managing the coating material on the screen mask.

[0018] In the above screen printing apparatus, the supply unit may be provided with the plurality of sensors, so that the third movement mechanism also functions as the first movement mechanism.

[0019] According to this configuration, a rational and compact configuration is achieved in which the third movement mechanism and the first movement mechanism are integrated.

[0020] In addition, in the above-mentioned screen printing device in which multiple sensors are moved integrally in a first direction, it is preferable that the multiple sensors are each arranged at a position where their detection positions can equally divide the width dimension of the squeegee in the first direction.

[0021] This configuration allows detection of the coating material at equal intervals in the longitudinal direction of the squeegee, which allows for balanced detection of the coating material by multiple sensors without being affected by the size of the squeegee, and is advantageous in terms of accurately determining whether or not the coating material needs to be supplied.

[0022] In addition, a screen printing apparatus according to another aspect of the present invention is characterized in that it comprises: a squeegee having a pressing surface extending in a first direction and moving a coating material along a screen mask via the pressing surface in a second direction perpendicular to the first direction; a detection unit consisting of a non-contact sensor that detects the coating material on the screen mask; a first movement mechanism that moves the detection unit in the first direction and a second movement mechanism that moves the detection unit in the second direction; and a control unit that controls the first and second movement mechanisms, obtains the width of the coating material in the first direction based on the detection of the coating material by the detection unit as it moves in the first direction, and performs a determination process on whether or not to supply the coating material based on the width.

[0023] According to this screen printing device, the longitudinal width (first-direction width) of the coating material on the screen mask pressed by the squeegee—specifically, the block of coating material arranged on the screen mask so as to extend in the first direction—is determined, and a determination is made as to whether or not to supply the coating material based on the determined width. That is, if a missing portion of the coating material occurs midway in the longitudinal direction, the width of the missing portion or the width of the divided coating material is determined, and a determination is made as to whether or not to supply the coating material based on this width. Therefore, compared to conventional devices that determine whether or not to supply the coating material by determining the width in the second direction from only one location on the coating material, the determination as to whether or not to supply the coating material can be made more accurately, and as a result, the coating material on the screen mask can be more appropriately managed. [Effects of the Invention]

[0024] According to the screen printing apparatus of the present invention as described above, it is possible to more appropriately manage the remaining amount of coating material on the screen mask. [Brief explanation of the drawings]

[0025] [Figure 1] 1 is a schematic side view of a screen printing apparatus according to a first embodiment. [Figure 2] FIG. 2 is a schematic front view (main part) of the screen printing apparatus. [Figure 3] FIG. 4 is a schematic side view illustrating the movement of a squeegee. [Figure 4] FIG. 2 is a plan view of a main part of a solder supply unit. [Figure 5] FIG. [Figure 6] FIG. 2 is a block diagram showing a control system of the screen printing apparatus. [Figure 7] 4 is a flowchart showing the operation control of the screen printing apparatus. [Figure 8] FIG. 10 is a conceptual plan view illustrating the operation of measuring the width of the solder roll. [Figure 9] 10A and 10B are schematic plan views illustrating the operation of the solder supplying process. [Figure 10] FIG. 10 is a conceptual plan view illustrating the operation of measuring the width of a solder roll in the second embodiment. [Figure 11] 10A and 10B are schematic plan views illustrating the operation of the solder supplying process. DETAILED DESCRIPTION OF THE INVENTION

[0026] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

[0027] [First embodiment] [Overall configuration of screen printing equipment] FIG. 1 is a side view showing the schematic configuration of a screen printing apparatus 1 (hereinafter abbreviated as printing apparatus 1) according to a first embodiment of the present invention, and FIG. 2 is a front view of the printing apparatus 1 (viewed from the X2 side). Note that in the figure, XYZ rectangular coordinates are shown to clarify directional relationships. The X direction is the horizontal direction, the Z direction is the vertical direction, and the Y direction is the direction perpendicular to both the X and Z directions. Note that the Y direction corresponds to the "first direction" of the present invention, and the X direction corresponds to the "second direction" of the present invention.

[0028] The printing apparatus 1 includes a printing work unit 2A that performs printing processing on a substrate P such as a printed circuit board, and a mask storage unit 2B that is disposed adjacent to the printing work unit 2A on the X1 side (one side in the X direction / the right side in FIG. 1). The mask storage unit 2B stores replacement screen masks.

[0029] The printing work section 2A is provided with a mask holding unit 3, a substrate holding unit 4, and a printing unit 5.

[0030] The substrate holding unit 4 includes an upper unit 4A and a lower unit 4B. The upper unit 4A holds the substrate P during printing operations and includes a conveyor 20 for transporting the substrate P, a substrate support mechanism 22 that lifts the substrate P from the conveyor 20 and supports it, and a substrate clamp mechanism 24 that clamps the substrate P lifted from the conveyor 20. The conveyor 20, the substrate support mechanism 22, and the substrate clamp mechanism 24 are operated by actuators such as motors and air cylinders. The substrate P is carried onto the conveyor 20 from the upstream side in the Y direction (the rear side in the direction perpendicular to the paper surface in FIG. 1 / the Y1 side in FIG. 2) and is held in a positioned state by the substrate support mechanism 22 and the substrate clamp mechanism 24 in the upper unit 4A. After the printing process, the substrate P is released from its positioned state and carried out downstream in the Y direction by the conveyor 20.

[0031] The lower unit 4B moves the substrate P positioned (held) by the upper unit 4A together with the upper unit 4A. Although details are omitted, the lower unit 4B is composed of a table and a table drive mechanism operated by the actuator that displaces the table in the X, Y, Z, and R directions. The R direction is the direction of rotation around the Z axis.

[0032] The upper unit 4A is fixed onto the table of the lower unit 4B. With this configuration, the substrate holding unit 4 is able to move the substrate P in each of the X, Y, Z and R directions.

[0033] The mask holding unit 3 is disposed above the substrate holding unit 4. The mask holding unit 3 holds a screen mask 6 (hereinafter abbreviated as mask 6). The mask 6 is rectangular (rectangular or square) in plan view, and is composed of a mask body 60 made of a thin metal plate in which printing openings (mask openings) are formed, and a metal (e.g., aluminum) frame 62 that holds the peripheral edge of the mask body 60.

[0034] The mask holding unit 3 includes a pair of guide members 26 that extend parallel to each other in the X direction and are spaced apart in the Y direction, and a mask clamp device (not shown) that clamps the mask 6 to the pair of guide members 26. The mask clamp device is actuated by the actuator.

[0035] Each guide member 26 is an L-shaped cross-section member that includes a support portion 27a that supports the mask 6 and a guide portion 27b that restrains the mask 6 from the outside in the Y direction, and is made of a metal material such as stainless steel. A mask clamp device is provided on each guide member 26 and is composed of a clamp plate and the actuator that drives the clamp plate forward and backward in the Z direction. The mask clamp device fixes the mask 6 to the guide member 26 by sandwiching the frame 62 of the mask 6 between the support portion 27a of the guide member 26 and the clamp plate. In the following description, unless otherwise specified, the term "mask 6" refers to the mask body 60.

[0036] The printing unit 5 is movably provided in the space above the mask holding unit 3. The printing unit 5 is a unit member that mainly moves the solder paste along the upper surface of the mask 6. The solder paste is an example of the coating material of the present invention, i.e., a semi-fluid material that is conductive and viscous.

[0037] The printing unit 5 is provided so as to be movable in the X direction by an X-axis drive mechanism 10. The printing unit 5 includes a beam 5a extending in the Y direction. The X-axis drive mechanism 10 (corresponding to the "second movement mechanism" of the present invention) is a screw feed mechanism including a pair of rails 12 extending in the X direction and movably supporting both ends of the beam 5a, a screw shaft 14 provided parallel to the rails 12 and threadedly inserted into a nut member (not shown) of the beam 5a, and a servo motor 15 that drives the screw shaft 14. In other words, the screw shaft 14 is rotationally driven by the servo motor 15, thereby moving the printing unit 5 in the X direction along the rails 12. Note that the X-axis drive mechanism 10 may be a mechanism other than a screw feed mechanism.

[0038] 1, the rail 12 and the screw shaft 14 extend from the end portion on the X2 side (the other side in the X direction / the left side in FIG. 1) of the printing work section 2A to the middle portion of the mask storage section 2B. This allows the printing unit 5 to move in the X direction from the end portion on the X2 side of the printing work section 2A to the middle portion of the mask storage section 2B.

[0039] The printing unit 5 is equipped with a squeegee 16 , a squeegee drive mechanism 17 , a mask slider 18 , a solder supply unit 7 , and a Y-axis drive mechanism 8 .

[0040] The squeegee 16 is a rectangular plate member elongated in the Y direction and having a flat pressing surface 16a that presses the solder paste. The pressing surface 16a is made of a polymer material such as urethane rubber, polyacetal, polyethylene, or polyester. The squeegee 16 moves back and forth in the X direction together with the printing unit 5. The solder paste on the mask 6, i.e., a mass of solder paste (referred to as a solder roll S) extending in the X direction on the mask 6, is pressed by the squeegee 16 via the pressing surface 16a, and moves in the X direction along the top surface of the mask 6.

[0041] The squeegee drive mechanism 17 is operated by the actuator to rotate the squeegee 16 about an axis extending in the Y direction and to raise and lower (move in the Z direction) the squeegee 16 relative to the beam 5a of the printing unit 5. Operation of the squeegee drive mechanism 17 moves the squeegee 16 between a position where it can slide against the mask 6 (the position shown by the two-dot chain line in FIG. 1) and a position where it retracts above the mask 6 (the position shown by the solid line in FIG. 1). Operation of the squeegee drive mechanism 17 also changes the posture of the squeegee 16 during forward and backward movements, as shown in FIG. 3, so that the pressing surface 16a faces forward in the direction of travel, and also changes the angle of the squeegee 16 relative to the mask 6. FIG. 3 is a schematic side view illustrating the movement of the squeegee.

[0042] The angle θ formed between the pressing surface 16a of the squeegee 16 and the upper surface of the mask body 60 is called the attack angle. The attack angle is set to an angle suitable for the printing process based on various conditions such as the type (properties) of solder, the opening area of ​​the mask 6, and the movement speed of the squeegee 16.

[0043] The mask slider 18 is a mask engagement device used to move the mask 6 between the printing work unit 2A and the mask storage unit 2B. The mask slider 18 includes a pin 18a extending in the Z direction and a pin driver 18b, such as an air cylinder, that drives the pin 18a forward and backward in the Z direction. The pin driver 18b operates to move the pin 18a between a protruding position (lowered position) where its tip (lower end) is lower than the top surface of the frame 62 of the mask 6 and a retracted position (upper position) where the pin 18a is retracted above the mask 6. In other words, the mask slider 18 hooks the pin 18a onto the frame 62, thereby moving the mask 6 in the X direction as the printing unit 5 moves. Note that FIG. 1 shows the mask slider 18 with the pin 18a displaced to the retracted position.

[0044] The mask storage section 2B is provided with a mask stocker 30 that stores multiple masks 6 in a removable manner, and an elevator mechanism (not shown) that raises and lowers (moves in the Z direction) the mask stocker 30. The mask stocker 30 has upper and lower storage sections 32a and 32b, and two types of masks 6 (6A and 6B) with different mask opening patterns are stored in these storage sections 32a and 32b.

[0045] The lifting mechanism is operated by the actuator and selectively positions either the first storage section 32a or the second storage section 32b at a predetermined mask replacement height position facing the guide member 26 in the X direction. Fig. 1 shows a state in which the lower storage section 32b is positioned at the mask replacement height position, and the mask 6B that was stored in storage section 32b is positioned in the printing work section 2A (guide member 26).

[0046] Solder supply unit 7 (corresponding to the "supply unit" of the present invention) is a device that supplies solder onto mask 6. Solder supply unit 7 is provided so as to be movable in the Y direction relative to beam 5a by Y-axis drive mechanism 8 (corresponding to the "first drive mechanism" of the present invention). Y-axis drive mechanism 8 is comprised of a screw feed mechanism or the like, and is driven by a motor (not shown) to move solder supply unit 7 in the Y direction, as shown in FIG. 2.

[0047] The solder supply unit 7 includes a unit frame 7a connected to the Y-axis drive mechanism, and a supply head 40 fixed to the unit frame 7a.

[0048] The supply head 40 has a cylindrical solder container 42 that extends vertically and has a solder discharge part 42a at its tip (bottom end). The solder discharge part 42a is a part that discharges the solder contained in the solder container 42 toward the mask 6. The solder discharge part 42a has a discharge port that opens and closes by actuation of a shutter member (not shown) by the actuator, and the amount of solder discharged (supplied) is controlled according to the open time of the discharge port.

[0049] A plurality of sensors 44a, 44b (detecting units) are arranged in a line in the Y direction on the unit frame 7a.

[0050] Each of the sensors 44a, 44b (referred to as the first sensor 44a and the second sensor 44b) is, for example, an optical reflective sensor (non-contact sensor) equipped with a light-emitting unit and a light-receiving unit. Each of the sensors 44a, 44b is used to measure the width of the solder roll S on the mask 6, specifically, the width of the solder roll S in the X direction. That is, each of the sensors 44a, 44b scans the upper surface of the mask 6 while irradiating the upper surface of the mask body 60 with light from the light-emitting unit as the printing unit 5 moves in the X direction. During the scan, the irradiated light is reflected by the mask 6 and enters the light-receiving unit at positions where the solder roll S is not present, whereas the irradiated light is scattered at positions where the solder roll S is present and does not enter the light-receiving unit. The solder supply control unit 102, which will be described later, calculates the width of the solder roll S based on the time during which each of the sensors 44a, 44b detects the solder roll S (the time during which the light-receiving unit receives the irradiated light) and the moving speed of the printing unit 5. This allows the width of the solder roll S to be measured.

[0051] 2 and 4, the sensors 44a and 44b are arranged at positions symmetrical in the Y direction with respect to the supply head 40. FIG.

[0052] The first sensor 44a is disposed on the Y2 side of the supply head 40, and the second sensor 44b is disposed on the Y1 side of the supply head 40. Each of the sensors 44a, 44b is fixed by a fixing member (a screw in this example) to a bracket 70 (see FIG. 4) provided on the unit frame 7a. Therefore, each of the sensors 44a, 44b moves in the Y direction together with the solder supply unit 7 as the solder supply unit 7 moves due to the operation of the Y-axis drive mechanism 8.

[0053] 4, guide plates 50 are provided on both sides of supply head 40 in the Y direction, adjacent to bracket 70. Guide plates 50 are guide members that guide movement of sensors 44a, 44b in the Y direction while positioning sensors 44a, 44b in the X direction.

[0054] The guide plate 50 has a rectangular shape in a plan view that is elongated in the Y direction, and is provided with slit-like (linear) guide holes 52 that extend in the Y direction. A pair of pins 45 aligned in the Y direction is erected on the upper surface of each of the sensors 44a, 44b, and each of the sensors 44a, 44b is fixed to the bracket 70 with screws with the pins inserted into the guide holes 52. In other words, the arrangement of the sensors 44a, 44b in the Y direction can be changed by loosening the screws and translating the sensors 44a, 44b along the guide plate 50 and the guide holes 52.

[0055] 2, when the solder supply unit 7 is placed at a predetermined measurement position Mp, the sensors 44a, 44b are positioned so that their detection positions Dp equally divide the width W (dimension in the Y direction) of the squeegee 16 in the same direction. Specifically, the measurement position Mp is a position where the supply head 40 (solder discharge portion 42a) is placed at the center position O (center position in the Y direction) of the squeegee 16. When the solder supply unit 7 is placed at the measurement position Mp, the positions of the sensors 44a, 44b in the Y direction are set so that their detection positions Dp equally divide the width W of the squeegee 16 into thirds.

[0056] As shown in FIG. 5, the guide plate 50 is marked with indicators 54 indicating the fixing positions of the sensors 44a, 44b corresponding to the size of the squeegee 16, etc. The indicators 54 include position indicators 55a and identification indicators 55b. The position indicators 55a are indicators indicating the fixing positions of the sensors 44a, 44b, and the identification indicators 55b are indicators indicating the type and size of the squeegee 16. The operator can fix the sensors 44a, 44b in positions that equally divide (third) the width dimension W of the squeegee 16 in the Y direction by aligning the reference position (e.g., the end face in the Y direction) of each sensor 44a, 44b with the position indicator 55a corresponding to the squeegee 16 to be set in the printing unit 5.

[0057] [Control system configuration] 6 is a block diagram showing a control system of the printing device 1. The printing device 1 is equipped with a control device 100 that performs overall control of the operation of the printing device 1.

[0058] The control device 100 is connected to a display unit 110 configured by, for example, a liquid crystal display, and an operation unit 120 configured by a keyboard, a mouse, a touch panel provided on the display unit 110, or the like.

[0059] The control device 100 is configured from a CPU (Central Processing Unit) and peripheral devices, and includes a print control unit 101, a solder supply control unit 102, a display control unit 103, and a storage unit 104 as its functional components.

[0060] The printing control unit 101 controls the operation of each part of the screen printing apparatus 1, such as the mask holding unit 3, the substrate holding unit 4, the X-axis drive mechanism 10, the squeegee drive mechanism 17, and the mask slider 18, in accordance with the program, production plan information, and production substrate data stored in the memory unit 104 to execute the printing process for the substrate P, and also performs various judgments and calculations required for the printing process. The program includes the conditions for the printing process (printing conditions). The printing conditions include, for example, the attack angle and printing speed described above. The printing speed is the movement speed of the squeegee 16 during the printing process.

[0061] The solder supply control unit 102 controls the operation of the sensors 44a, 44b, solder supply unit 7, Y-axis drive mechanism 8, and X-axis drive mechanism 10 in accordance with programs stored in the memory unit 104 to perform a roll width measurement process for measuring the width of the solder roll S and a process for supplying solder onto the mask 6 (solder supply process), and also performs various judgments and calculations required for the solder supply process.

[0062] [Operation control of printing device 1] 7 is a flowchart showing the operational control of the printing device 1. When this flowchart starts, the printing control unit 101 executes the printing process (steps S1 and S3).

[0063] Specifically, the printing control unit 101 controls the substrate holding unit 4 to first load the substrate P into the machine and hold it with the upper unit 4A, and then have the lower unit 4B place the substrate P on the underside of the mask 6. Next, the printing control unit 101 controls the X-axis drive mechanism 10 and the squeegee drive mechanism 17 to position the squeegee 16 at a movement start position on the mask 6 and then move the squeegee 16 along the mask 6 from the movement start position. This movement causes the solder roll S on the mask 6 to move with the squeegee 16, applying (printing) solder to the substrate P through the mask opening. When the squeegee 16 reaches the movement end position, the printing control unit 101 raises the squeegee 16 and changes its orientation so that the pressing surface 16a faces away from the mask 6 in preparation for the next printing process (see FIG. 3). At the same time, the printing control unit 101 controls the substrate holding unit 4 to move the substrate P downward away from the mask 6 and then transport the printed substrate P out of the machine. This completes the printing process.

[0064] When the printing process is completed, the solder supply control unit 102 controls the Y-axis drive mechanism 8 to place the solder supply unit 7 at the measurement position Mp (step S5). As a result, the sensors 44a and 44b are positioned so as to divide the width W of the squeegee 16 into thirds.

[0065] Next, the solder supply control unit 102 executes a roll width measurement process (step S7). That is, the solder supply control unit 102 controls the X-axis drive mechanism 10 to move the sensors 44a and 44b in the X direction together with the solder supply unit 7 (printing unit 5). As a result, the sensors 44a and 44b scan the mask 6, thereby measuring the width of the solder roll S in the X direction at two points spaced apart in the Y direction (longitudinal direction).

[0066] When the measurement is completed, the solder supply control unit 102 determines whether solder supply is necessary. Specifically, the solder supply control unit 102 determines whether each measurement width is less than a set value (step S9). The set value is, for example, a value calculated from the amount of solder supplied onto the mask 6 at the start of the printing process (initial solder amount), the average consumption amount which is the average amount of solder consumed in one printing process, and the total number of printing processes from the first to the time of measurement. In this case, the set value for the measurement width based on detection by the first sensor 44a and the measurement value for the measurement width based on detection by the second sensor 44b may be the same value or different values. For example, if the area of ​​the mask opening is biased to one side in the Y direction with respect to the center line of the mask 6, the respective set values ​​may be different values.

[0067] If the determination in step S9 is Yes, the solder supply control unit 102 executes the solder supply process by controlling the Y-axis drive mechanism 8, the X-axis drive mechanism 10, and the solder supply unit 7 (step S11). Specifically, the solder supply control unit 102 identifies, among the detection positions Dp of the sensors 44a and 44b on the solder roll S, a location where there is a shortage of solder, i.e., a location where the measured width is less than a set value, moves the supply head 40 to the location where there is a shortage, and causes the solder discharge unit 42a to discharge solder to the location where there is a shortage. In this case, the solder supply control unit 102 not only discharges (supplies) a preset amount of solder, but also calculates a supply amount based on the deviation between the measured width and the set value, and causes the calculated amount of solder to be discharged.

[0068] For example, as shown in Fig. 8, if there is a shortage of solder at position Dp of the solder roll S detected by the second sensor 44b, the solder supply control unit 102 moves the supply head 40 to the shortage location Sp to dispense solder. In this case, the solder supply control unit 102 not only stops the supply head 40 at the solder shortage location Sp, i.e., position Dp detected by the second sensor 44b, and dispenses solder, but also, as shown in Fig. 9, moves the supply head 40 in the Y direction so that equal amounts of solder are dispensed on both sides of the detection position Dp in the Y direction, a predetermined distance L.

[0069] If the determination in step S9 is No, that is, if the measurement width is equal to or greater than the set value, the solder supply control unit 102 skips step S9 and proceeds to step S11.

[0070] When the solder supply process is completed, the print control unit 101 determines whether or not the production of the boards P is completed, that is, whether or not the printing process for a specified number of boards P, for example, one production lot, has been completed (step S13). If the determination here is Yes, the print control unit 101 ends this flowchart, but if the determination here is No, the process returns to step S1.

[0071] [Action and effect] As described above, in the printing device 1 of the first embodiment, the printing unit 5 (solder supply unit 7) is provided with the first sensor 44a and second sensor 44b, which are non-contact sensors aligned in the Y direction. As the printing unit 5 moves in the X direction, the solder supply control unit 102 measures the width of the solder roll S at the detection positions Dp of the sensors 44a and 44b, and determines whether solder supply is necessary based on these measured widths (steps S5 to S9).

[0072] Therefore, the printing device 1 can more accurately determine whether solder needs to be supplied than conventional devices that measure the width of the solder roll at only one point in its longitudinal direction to determine whether solder needs to be supplied, and as a result, it becomes possible to more appropriately manage the solder roll S on the mask 6.

[0073] In particular, when the solder supply unit 7 is positioned at the measurement position Mp, the sensors 44a, 44b are positioned so that their detection positions Dp are positions that equally divide (thirds) the width dimension W (dimension in the Y direction) of the squeegee 16 in the same direction, allowing the sensors 44a, 44b to measure the width of the solder roll S in a well-balanced manner. Therefore, with the printing device 1, it is possible to more accurately determine whether solder supply is required compared to when the width of the solder roll S is measured at a position offset in the longitudinal direction.

[0074] Moreover, the printing device 1 is provided with a guide plate 50 on which are marked indices 54 corresponding to the size of the squeegee 16, and by fixing the sensors 44a, 44b to the bracket 70 according to the indices 54, the sensors 44a, 44b can be easily positioned at positions that divide the width dimension W of the squeegee 16 equally (into thirds) in the Y direction. Therefore, the printing device 1 has the advantage that the width of the solder roll S can always be measured in a balanced manner at two locations in the longitudinal direction (Y direction) regardless of the size of the squeegee 16.

[0075] Furthermore, in the printer 1, the solder supply unit 7 is movable in the Y direction by the Y-axis drive mechanism 8. This configuration allows solder to be supplied directly and quickly to the solder shortage area of ​​the solder roll S, i.e., the detection position Dp detected by the sensors 44a and 44b. Furthermore, by discharging solder while moving the solder supply unit 7 in the Y direction, solder can be supplied over a predetermined distance L including the detection position Dp (see FIG. 9), providing a high degree of freedom in the solder supply process. Therefore, the printer 1 allows for more appropriate management of the solder roll S on the mask 6 by executing the solder supply process in a manner corresponding to the measurement width.

[0076] [Second embodiment] Next, we will explain the printing device 1 of the second embodiment. The basic configuration of the printing device 1 of the second embodiment is the same as that of the printing device 1 of the first embodiment, but the printing device 1 of the second embodiment differs from the printing device 1 of the first embodiment mainly in the following specific content of the operation control (FIG. 7).

[0077] In the first embodiment, the measurement position Mp, i.e., the position (coordinate) in the Y direction where the solder supply unit 7 is placed when measuring the width of the solder roll S, is fixed, and the measurement position Mp is the position where the detection positions Dp of the sensors 44a, 44b divide the width dimension W of the squeegee 16 into thirds. However, in the second embodiment, for example, a plurality of measurement positions Mp are set in the Y direction as the measurement position Mp.

[0078] In the processing of step S5 in Figure 7, the solder supply control unit 102 places the solder supply unit 7 at the first measurement position Mp, and in the processing of step S7, as shown in Figure 10, moves the solder supply unit 7 sequentially to adjacent measurement positions Mp, causing each of the first sensor 44a and the second sensor 44b to detect the solder roll S at multiple different positions in the Y direction.

[0079] Specifically, the solder supply control unit 102 alternately performs a scanning operation (X-direction arrow) in which the sensors 44a, 44b are moved in the X direction together with the solder supply unit 7 to detect the solder roll S, and a sliding operation (Y-direction arrow) in which the sensors 44a, 44b are moved in the Y direction. As a result, the first sensor 44a scans four different positions on the solder roll S in an area Ar1 on the Y2 side of the center position O of the squeegee 16, and the second sensor 44b scans four different positions on the area Ar2 on the Y1 side of the center position O of the squeegee 16. As a result, the solder supply control unit 102 measures the width of the solder roll S at a total of eight positions in the longitudinal direction (Y direction).

[0080] 10, the first measurement position Mp is a position where the first sensor 44a is arranged near the end of the squeegee 16 (solder roll S) on the Y2 side, and the second sensor 44b is arranged near the center of the squeegee 16 (solder roll S) in the Y direction (arrows on the right ends of each of areas Ar1 and Ar2 in FIG. 10). The final measurement position Mp is a position where the first sensor 44a is arranged near the center of the squeegee 16 in the Y direction, and the second sensor 44b is arranged near the end of the squeegee 16 on the Y1 side (arrows on the left ends of each of areas Ar1 and Ar2 in FIG. 10).

[0081] In the processing of step S7, the solder supply control unit 102 moves (slides) the solder supply unit 7 toward the Y1 side a fixed distance from the first measurement position Mp to the final measurement position Mp a total of three times, and measures the width of the solder roll S at a total of eight positions, as described above.

[0082] If the determination in step S9 is Yes, the solder supply control unit 102 executes the solder supply process (step S11). In this case, the solder supply control unit 102 moves the supply head 40 to a position where there is a shortage of solder among the detection positions Dp of the sensors 44a, 44b, and causes the solder discharge unit 42a to discharge solder to the shortage portion.

[0083] For example, as shown in FIG. 10, if there is a shortage of solder at multiple adjacent detection positions Dp on the solder roll S detected by the second sensor 44b, the solder supply control unit 102 can simply move the supply head 40 in the Y-axis direction and cause solder to be ejected from the supply head 40 at each detection position Dp, or as shown in FIG. 11, can move the supply head 40 continuously in the Y-axis direction and eject solder across the multiple detection positions Dp.

[0084] As described above, in the printing device 1 of the second embodiment, the solder supply unit 7 is moved to multiple measurement positions Mp, causing each of the first sensor 44a and the second sensor 44b to detect the solder roll S at multiple mutually different positions in the Y direction. This allows the width of the solder roll S to be measured in more detail along its length, making it possible to more accurately determine whether solder supply is necessary, and as a result, it becomes possible to more appropriately manage the solder roll S on the mask 6.

[0085] In particular, the printing device 1 measures the width of the solder roll S at multiple positions by alternately performing a scanning operation (X-direction arrow) in which the sensors 44a, 44b are moved together in the X direction along with the solder supply unit 7 to detect the solder roll S, and a sliding operation (Y-direction arrow) in which the sensors 44a, 44b are moved together in the Y direction. This allows the two sensors 44a, 44b to efficiently detect the solder roll S at different positions in the Y direction. In other words, the printing device 1 makes it possible to efficiently measure the width of the solder roll S while accurately determining whether solder supply is required.

[0086] In the second embodiment, as described above, the solder supply control unit 102 changes the measurement position Mp multiple times for each roll width measurement process in step S7. That is, for each printing process (for one substrate), the width of the solder roll S is measured at multiple locations (eight locations) as shown in FIG.

[0087] However, the solder supply control unit 102 may change the measurement position Mp only once for each printing process (for each substrate), i.e., for each process of step S5. For example, if the printing process in which the squeegee 16 is moved from the X1 side to the X2 side is defined as forward printing, and the printing process in which the squeegee 16 is moved from the X2 side to the X1 side is defined as return printing, and further, if the first printing process is defined as forward printing, the solder supply control unit 102 may measure the width of the solder roll S as follows.

[0088] First, after the first printing process (forward printing), the solder supply unit 7 is placed at the first measurement position Mp and the roll width measurement process is performed, and after the next printing process (returning printing), the solder supply unit 7 is moved from the first measurement position Mp to the next measurement position Mp and the roll width measurement process is performed. Then, after the next printing process (forward printing), the measurement position Mp is changed again from the previous measurement position Mp, and in this manner, the position of the solder supply unit 7 (measurement position Mp) may be moved a fixed distance toward the Y1 side for each printing process, i.e., for each process of step S5, and the roll width measurement process may be performed.

[0089] In this case, after reaching the final measurement position Mp, the solder supply unit 7 is reset to the initial measurement position Mp, and in the same manner, the position of the solder supply unit 7 (measurement position Mp) may be moved again from the initial measurement position Mp toward the Y1 side, or the position of the solder supply unit 7 (measurement position Mp) may be moved in the opposite direction from the final measurement position Mp, i.e., toward the Y2 side.

[0090] According to the configuration for executing the roll width measurement process in step S7 in this manner, since it is not necessary to change the measurement position Mp multiple times for each printing process, the processing time for step S7 can be kept at the same level as in the first embodiment, while changing the measurement position Mp for each printing process makes it possible to measure the width of the solder roll S in more detail along its length. Therefore, even with this configuration, it is possible to more accurately determine whether solder supply is necessary, and ultimately to more appropriately manage the solder roll S on the mask 6.

[0091] In the second embodiment (and its modified examples), the Y-axis drive mechanism 8 corresponds to the "third movement mechanism" of the present invention.

[0092] [Modifications, etc.] The printing apparatus 1 described above is an example of a preferred embodiment of the screen printing apparatus according to the present invention, and its specific configuration can be changed as appropriate without departing from the spirit of the present invention. For example, the following configurations and appropriate combinations of such configurations are also applicable.

[0093] (1) In the first and second embodiments, two sensors 44a, 44b are provided aligned in the Y direction to detect the solder roll S, but the number of sensors is not limited to two and may be three or more.

[0094] (2) In the first embodiment, the sensors 44a, 44b are provided on the solder supply unit 7 and are movable in the Y direction together with the solder supply unit 7. However, the sensors 44a, 44b may be fixedly provided on the beam 5a of the printing unit 5, for example. Also, in the first embodiment, the sensors 44a, 44b are arranged so that their detection positions Dp equally divide (thirds) the width dimension W of the squeegee 16, but other arrangements are also possible. For example, if the tendency for areas of solder deficiency to occur is known, the sensors 44a, 44b may be arranged at positions corresponding to those areas.

[0095] (3) In the second embodiment (and its modified example), the solder supply unit 7 (measurement position Mp) is moved a fixed distance in the Y direction, causing each of the first sensor 44a and the second sensor 44b to detect the solder roll S at multiple different positions in the Y direction. However, the movement distance of the solder supply unit 7, i.e., the interval between the measurement positions Mp, does not necessarily need to be constant. For example, in a specific region in the longitudinal direction of the solder roll S (squeegee 16), the measurement positions Mp may be set so that the interval (scanning interval) between the detection positions Dp of one sensor 44a (44b) is narrower than in other regions. This configuration makes it possible to detect the degree of solder reduction in a specific portion of the solder roll S in more detail.

[0096] (4) In the second embodiment (and its modified example), when changing the measurement position Mp, the solder supply unit 7 is moved by a fixed distance in the Y direction, i.e., the multiple measurement positions Mp are set at equal intervals. However, the intervals between the multiple measurement positions Mp, in other words, the scanning interval (scanning pitch) by each of the sensors 44a, 44b, may be configured so that the operator can arbitrarily set them. Specifically, the operator may input information regarding the scanning pitch of each of the sensors 44a, 44b via the operation unit 120, and the solder supply control unit 102 may execute the processes of steps S5 and S7 (move the solder supply unit 7) based on the input information.

[0097] (5) In the first embodiment, the width of the solder roll S in the X direction is measured, and the need for solder supply is determined based on the measured width. However, the width of the solder roll S in the Y direction may be measured, and the need for solder supply may be determined based on the measured width. Specifically, in the processing of steps S5 and S7 in Fig. 7, the solder supply unit 7 is moved in the Y direction with the sensors 44a and 44b positioned at the solder roll S in the X direction, and the sensors 44a and 44b scan the solder roll S in the Y direction. In this case, it is preferable to move the first sensor 44a or the second sensor 44b from the outside of the solder roll S (outside in the Y direction), for example.

[0098] This configuration makes it possible to detect missing portions of the solder roll S. That is, when the squeegee 16 is raised to separate it from the solder roll S, if a part of the solder roll S adheres to the pressing surface 16a and is completely lost, it becomes possible to detect the width of the missing portion (width in the Y direction) or the width of the divided solder roll S (width in the Y direction) (corresponding to the "width in the first direction related to the coating material" of the present invention). Therefore, by determining whether or not solder supply is required based on the measured width in the processing of step S9, it becomes possible to appropriately manage the solder roll S on the mask 6.

[0099] In this case, it is sufficient to use only one sensor to detect the solder roll S. However, a configuration including two sensors 44a and 44b can shorten the travel distance of the solder supply unit 7, thereby improving the efficiency of the measurement process. [Explanation of symbols]

[0100] 1 Screen printing equipment 5 Printing Unit 6 Screen Mask 7 Solder supply unit (supply unit) 8 Y-axis drive mechanism (first movement mechanism, third movement mechanism) 10 X-axis drive mechanism (second movement mechanism) 16 Squeegee 16a Pressing surface 17 Squeegee drive mechanism 44a First sensor (detection unit) 44b Second sensor (detection unit) 100 control device 101 Printing control unit 102 Solder supply control unit (control unit) 103 Display control unit 104 Storage section 110 Display section 120 Operation section S Solder roll (coating material)

Claims

1. a squeegee having a pressing surface extending in a first direction and moving the coating material along the screen mask via the pressing surface in a second direction perpendicular to the first direction; a detection unit that detects the coating material on the screen mask; a movement mechanism that moves the detection unit in the second direction; a control unit that controls the movement mechanism unit, calculates a width of the coating material in the second direction based on the detection of the coating material by the detection unit accompanying the movement in the second direction, and performs a process of determining whether or not the coating material needs to be supplied based on the width; the detection unit includes a plurality of sensors each consisting of a non-contact sensor and arranged in the first direction; The screen printing device, wherein the control unit determines the width of the coating material at the detection position of each of the plurality of sensors, and performs the determination process based on the width.

2. 2. The screen printing apparatus according to claim 1, a supply unit that is configured to move together with the plurality of sensors in the second direction by the second movement mechanism when the movement mechanism is defined as a second movement mechanism and that is capable of supplying a coating material onto the screen mask; a first moving mechanism that moves the supply unit in the first direction, The control unit further controls the first moving mechanism and the supply unit, and when it is determined in the necessity determination process that supply of coating material is necessary, identifies an area on the screen mask where there is a shortage of coating material, and moves the supply unit in the first direction to supply coating material to the area where there is a shortage.

3. 3. The screen printing apparatus according to claim 1, The screen printing apparatus according to claim 1, wherein the plurality of sensors are disposed such that their detection positions equally divide the width dimension of the squeegee in the first direction.

4. 2. The screen printing apparatus according to claim 1, When the movement mechanism is defined as a second movement mechanism, the sensor further includes a first movement mechanism that moves the plurality of sensors integrally in the first direction, The screen printing apparatus, wherein the control unit further controls the first movement mechanism unit.

5. 5. The screen printing apparatus according to claim 4, The control unit alternately performs a scanning operation that moves the plurality of sensors in the second direction to detect the coating material, and a sliding operation that moves the plurality of sensors in the first direction, thereby causing each of the plurality of sensors to detect the coating material at a plurality of different positions in the first direction.

6. 6. The screen printing apparatus according to claim 5, a supply unit that moves together with the plurality of sensors in the second direction by the second movement mechanism and is capable of supplying a coating material onto the screen mask; a third movement mechanism that moves the supply unit in the first direction; The control unit further controls the third movement mechanism and the supply unit, and when it is determined in the necessity determination process that supply of coating material is necessary, identifies an area on the screen mask where there is a shortage of coating material, and moves the supply unit to supply coating material to the area where there is a shortage.

7. 7. The screen printing apparatus according to claim 6, The screen printing apparatus, wherein the supply unit is provided with the plurality of sensors, so that the third movement mechanism also functions as the first movement mechanism.

8. The screen printing apparatus according to any one of claims 4 to 7, The screen printing apparatus, characterized in that the plurality of sensors are each disposed at a position such that their detection positions can equally divide the width dimension of the squeegee in the first direction.

9. a squeegee having a pressing surface extending in a first direction and moving the coating material along the screen mask via the pressing surface in a second direction perpendicular to the first direction; a detection unit that includes a non-contact sensor and detects the coating material on the screen mask; a first moving mechanism that moves the detection unit in the first direction and a second moving mechanism that moves the detection unit in the second direction; a control unit that controls the first and second movement mechanism units, obtains the width of the coating material in the first direction based on the detection of the coating material by the detection unit as the coating material moves in the first direction, and performs a process to determine whether or not the coating material needs to be supplied based on the width.

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