Printing device and viscosity measurement method

Abstract

To provide a printing device capable of obtaining a measurement value with high reliability during production of a substrate.SOLUTION: A printing device which prints a solder paste onto a substrate through a mask with a predetermined opening pattern includes: a suction unit that introduces the solder paste on the mask from a suction inlet and discharges it from an opening; a measurement unit that measures the viscosity or a viscosity-equivalent value of the solder paste introduced into the suction unit multiple times; and a control unit that causes the measurement unit to measure the viscosity or viscosity-equivalent value of the solder paste when a first predetermined time has elapsed from the previous measurement by the measurement unit.SELECTED DRAWING: Figure 9

Description

[Technical field]

[0001] The present disclosure relates to a printing apparatus and a viscosity measuring method. [Background technology]

[0002] Conventionally, there is known a screen printing apparatus that prints cream solder on a circuit board through a through hole in a mask by moving the cream solder placed on the mask along the mask with a squeegee. The screen printing apparatus of Patent Document 1 includes a viscosity detection device that detects a viscosity corresponding amount corresponding to the viscosity of the cream solder placed on the mask, and a screw cleaning device that cleans the screw serving as a detector of the viscosity detection device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2008-307864 A Summary of the Invention [Problem to be solved by the invention]

[0004] When the viscosity detection device of Patent Document 1 is a type that takes cream solder into the viscosity detection device and measures the viscosity of the cream solder, the cream solder remaining inside the viscosity detection device may deteriorate. If the cream solder remaining inside the viscosity detection device mixes with the cream solder to be measured next time, it is difficult to obtain an appropriate value as the viscosity corresponding amount corresponding to the viscosity of the cream solder. In other words, it is difficult to obtain a reliable measurement value during the production of circuit boards, and there is room for improvement.

[0005] The present disclosure has been made in consideration of the above circumstances, and provides a printing apparatus and a viscosity measurement method that can obtain highly reliable measured values ​​during the production of substrates. [Means for solving the problem]

[0006] One aspect of the present disclosure is a printing device that prints solder paste on a substrate through a mask having a predetermined opening pattern, the printing device having an suction section that can introduce the solder paste on the mask through an inlet and discharge it through an opening, a measurement section that measures the viscosity or a viscosity equivalent value of the solder paste introduced to the suction section multiple times, and a control section that causes the measurement section to measure the viscosity or the viscosity equivalent value of the solder paste when a first predetermined time has elapsed since the previous measurement by the measurement section.

[0007] One aspect of the present disclosure is a viscosity measurement method that uses a suction unit to measure the viscosity of a solder paste printed on a substrate through a mask having a predetermined opening pattern, the suction unit being capable of introducing the solder paste on the mask through an inlet and discharging it through an opening, the viscosity measurement method having an introduction step of introducing the solder paste on the mask into the suction unit, a measurement step of measuring the viscosity or a viscosity equivalent value of the solder paste introduced to the suction unit multiple times, and a control step of causing the measurement step to measure the viscosity or the viscosity equivalent value of the solder paste when a first predetermined time has elapsed since the previous measurement by the measurement step. Effect of the Invention

[0008] The present disclosure allows for reliable measurements to be taken during production of a substrate. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a side view (part 1) illustrating a configuration example of a main part of a printing device according to an embodiment of the present disclosure. [Diagram 2] Side view of the main part showing an example of the configuration of a printing device (part 2) [Diagram 3] FIG. 1 is a side view showing an example of the configuration of a portion of a print head provided in a printing device; [Figure 4A] FIG. 1 is a diagram showing an example of a state in which a printing device is performing a printing operation. [Figure 4B]FIG. 2 is a diagram showing an example of a state in which a printing device is performing a printing operation. [Diagram 5] FIG. 1 is a side view showing a state in which the viscosity of the solder paste is measured by a viscometer provided in the printing device. [Figure 6] FIG. 1 is a diagram for explaining measurement of the viscosity of solder paste using a viscometer. [Figure 7] FIG. 1 shows an example of where a viscometer is placed relative to the solder paste. [Figure 8A] FIG. 1 is a block diagram showing an example of the configuration of a control system in a printing device. [Figure 8B] FIG. 13 is a diagram showing an example of a table for storing information on a reference time T1; [Figure 8C] FIG. 13 is a diagram showing an example of a table for storing information on cleaning notification time T2. [Figure 9] 1 is a flowchart showing an example of the operation of a printing device; [Figure 10] Flowchart showing an example of a viscosity measurement process [Figure 11] Flowchart showing an example of operation related to viscometer state management [Figure 12] 1 is a flowchart showing an example of a solder paste replacement process. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, the embodiments of the present disclosure will be described in detail with reference to the drawings as appropriate. However, more detailed description than necessary may be omitted. For example, detailed description of already well-known matters and duplicated description of substantially the same configuration may be omitted. This is to avoid the following description becoming unnecessarily redundant and to facilitate understanding by those skilled in the art. Note that the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present disclosure, and are not intended to limit the subject matter described in the claims.

[0011] For example, the term "unit" or "device" in the embodiments is not limited to a physical configuration that is mechanically realized by hardware, but also includes a configuration whose functions are realized by software such as a program. Also, the functions of one configuration may be realized by two or more physical configurations, or the functions of two or more configurations may be realized by, for example, one physical configuration.

[0012] (One embodiment) 1 and 2 are side views of essential parts showing a configuration example of a printing device 1 according to an embodiment of the present disclosure.

[0013] In this embodiment, the substrate transport direction (the depth direction in FIG. 1) is defined as the X direction, the direction perpendicular to the X direction in the horizontal plane (the left-right direction in FIG. 1) is defined as the Y direction, and the direction perpendicular to the horizontal plane (the up-down direction in FIG. 1) is defined as the Z direction.

[0014] The printing device 1 is a device that prints solder paste Pst on a board KB and sends it to a downstream component mounting device. The printing device 1 includes a mask 11, a board support unit 12, a print head 13, a head moving mechanism 14, a viscometer 15, a viscometer moving unit 16, and a control device 17.

[0015] In FIG. 1, the mask 11 is made of a thin metal plate member or a sheet-like member such as cloth or resin that extends in a horizontal plane. As shown in FIG. 2 and FIG. 7, the mask 11 has a predetermined opening pattern 11K corresponding to the arrangement of a plurality of electrodes DK provided on the substrate KB. The opening pattern 11K is formed in a pattern area in the center of the mask 11. The substrate support part 12 holds the substrate KB and positions the substrate KB with respect to the mask 11. The substrate support part 12 includes a substrate support table 12a on which the substrate KB is placed and supported, and a side clamper 12b that clamps the side surface of the substrate KB in the Y direction to fix the position. The side clamper 12b is made of a pair of block-like members arranged in the horizontal direction (Y direction). The pair of side clampers 12b holds the substrate KB by sandwiching it from its sides (Y direction) when it is transported in a direction perpendicular to the Y direction (X direction). The substrate support table 12a supports the substrate KB at a position where the height of the upper surface of the substrate KB is the same as the height of the upper surfaces of the pair of side clampers 12b (FIG. 2).

[0016] The substrate support part 12 holding the substrate KB is raised and its horizontal position is adjusted by a moving mechanism (not shown) (Fig. 2 → Fig. 1). As a result, the substrate KB is positioned with respect to the mask 11 and brought into contact with or close to the lower surface of the mask 11, and each electrode DK is positioned so as to overlap the corresponding opening pattern 11K in the horizontal direction (Fig. 1). This makes the substrate support part 12 ready for the "printing operation" described below. Such an operation for making the substrate support part 12 ready for the "printing operation" is called a "printing preparation operation."

[0017] 1, the print head 13 is provided with two lift cylinders 22 and two squeegee units 23 on a base portion 21. The base portion 21 is a member extending horizontally and is movable in the Y direction in the space above the mask 11. The two lift cylinders 22 are provided on the base portion 21 and arranged opposite each other in the Y direction, and each has a piston rod 22R protruding below the base portion 21.

[0018] The two squeegee units 23 are attached to the piston rods 22R of the two lift cylinders 22. Therefore, by individually operating the two lift cylinders 22, the two squeegee units 23 can be raised and lowered relative to the base portion 21.

[0019] FIG. 3 is a side view showing an example of the configuration of a portion of the print head 13 provided in the printing device 1. As shown in FIG.

[0020] 3, each squeegee unit 23 includes a squeegee holder 31, a squeegee 32, and an attack angle changing section 33. The squeegee holder 31 is made up of a fixed section 41 and a movable section 42. The fixed section 41 is attached to the lower end of the piston rod 22R. The movable section 42 has its upper end connected to the fixed section 41 and is freely swingable about a hinge shaft 42J that is parallel to the X-axis.

[0021] The squeegee 32 is made of a flat (spatula-shaped) member. The upper edge side of the squeegee 32 is held by the squeegee holder 31, which extends obliquely below the squeegee 32. The two squeegee units 23 are attached in such a manner that the squeegees 32 face each other in the Y direction and the distance between them increases toward the lower edge sides (FIG. 1). The elevation angle of each squeegee 32 from the horizontal plane is called the attack angle θ.

[0022] The attack angle change section 33 is an actuator that swings the movable section 42 around the hinge shaft 42J. Each squeegee unit 23 can change the attack angle θ of the squeegee 32 by operating the attack angle change section 33. The squeegee 32 shown by the dashed line in Fig. 3 (referred to as "32a") shows a case in which the attack angle θ is larger than that of the squeegee 32 shown by the solid line, and the squeegee 32 shown by the dashed line in Fig. 3 (referred to as "32b") shows a case in which the attack angle θ is smaller than that of the squeegee 32 shown by the solid line.

[0023] The head moving mechanism 14 is composed of, for example, a table mechanism, and moves the print head 13 in the Y direction. When the head moving mechanism 14 moves the print head 13 in the Y direction, the squeegee unit 23 moves in the Y direction.

[0024] 4A and 4B are diagrams showing an example of a state in which the printing device is performing a printing operation, in which the illustration of the substrate support portion 12 is partially omitted.

[0025] When the solder paste Pst is printed on the electrodes DK of the substrate KB by the print head 13, first, the substrate KB is brought into contact with or close to the lower surface of the mask 11 by the above-mentioned "print preparation operation". Then, one of the two squeegees 32 is lowered by the lift cylinder 22, and the lower edge of the lowered squeegee 32 is brought into contact with the upper surface of the mask 11. Then, the print head 13 is moved horizontally by the head moving mechanism 14. At this time, the direction in which the print head 13 is moved is the direction in which the squeegee 32 on the side in contact with the mask 11 moves toward the squeegee 32 on the other side.

[0026] When the print head 13 moves horizontally, the squeegee 32, whose lower end is in contact with the mask 11, slides over the mask 11. As a result, the solder paste Pst on the mask 11 is scraped up by the squeegee 32 (FIG. 4A → FIG. 4B) and pushed (filled) into the opening pattern 11K, so that the solder paste Pst is printed on the electrodes DK of the substrate KB (FIG. 4B). Hereinafter, the operation of the print head 13 to print the solder paste Pst on the electrodes DK of the substrate KB through the opening pattern 11K of the mask 11 in this manner will be referred to as the "printing operation."

[0027] In the printing operation by the print head 13, the squeegee 32 moves the solder paste Pst from a position corresponding to one side clamper 12b to a position corresponding to the other side clamper 12b. This causes the solder paste Pst to be printed onto the multiple electrodes DK of the substrate KB. After the printing operation is completed, a moving mechanism (not shown) lowers the substrate support part 12 to separate the substrate KB from the mask 11, performing a "plate separation operation" (FIG. 1 → FIG. 2).

[0028] In the above printing operation, the printer 1 can adjust the state (printing state) of the solder paste Pst printed on the electrodes DK of the substrate KB by changing the printing conditions. Here, the "printing state" refers to the thickness and shape of the solder paste Pst printed on the electrodes DK, and the "printing conditions" include the attack angle θ, the movement speed of the print head 13 (i.e., the squeegee 32), the pressing force of the squeegee 32 against the mask 11, and the like.

[0029] 5 is a side view showing a state in which the viscosity or viscosity equivalent value (hereinafter referred to as viscosity, etc.) of the solder paste Pst is being measured by a viscometer 15 provided in the printing device 1. The viscosity equivalent value is a value equivalent to a viscosity related to viscosity, and is, for example, a measured value equivalent to a viscosity measured under conditions at least partially different from the measurement conditions specified as the measurement conditions for viscosity measurement by the JIS standard. Note that in FIG. 5, the illustration of the board support part 12 is partially omitted.

[0030] 1 and 5, the viscometer 15 is a measuring device that measures the viscosity of the solder paste Pst supplied to the mask 11. The viscometer 15 is attached to the base portion 21 of the print head 13 via a viscometer moving portion 16. The detailed configuration of the viscometer 15 will be described later.

[0031] 1 and 5, the viscometer moving unit 16 includes a base side member 16a attached to the base portion 21 of the print head 13, a viscometer holding member 16b that holds the viscometer 15, and an X-direction moving mechanism 16c that moves the base side member 16a in the X-direction along the base portion 21. The viscometer holding member 16b is movable up and down relative to the base side member 16a, and is raised and lowered relative to the base side member 16a by an actuator (not shown), causing the viscometer 15 to protrude below the print head 13. The X-direction moving mechanism 16c is capable of moving the portion placed on the base side member 16a, i.e., the viscometer 15, in the X-direction.

[0032] FIG. 6 is a diagram for explaining the measurement of the viscosity and the like of the solder paste Pst using a viscometer 15. As shown in FIG.

[0033] The viscometer 15 has a screw 151, a cylindrical body 152, and a torque sensor 153. The screw 151 is capable of coming into contact with the solder paste Pst and extends along the Z direction. As an example, the screw 151 does not rotate around an axis in the Z direction.

[0034] The cylindrical body 152 covers the screw 151 from the outside of the XY plane. That is, the screw 151 is contained within the cylindrical body 152. The cylindrical body 152 has, for example, a cylindrical shape (cylinder shape). The cylindrical body 152 rotates around an axis in the Z direction, for example. The cylindrical body 152 has an introduction section 154 with a part of the lower part of the cylindrical body 152 open. The introduction section 154 may be provided, for example, at the lower end of the cylindrical body 152 in the Z direction, or below the side end of the cylindrical body 152. The introduction section 154 contacts the solder paste Pst on the mask 11 to introduce the solder paste Pst. The introduction section 154 has a suction port that sucks in the solder paste. The cylindrical body 152 has a discharge section 155 with a part of the upper part of the cylindrical body 152 open. The discharge portion 155 may be provided, for example, at the upper end portion in the Z direction of the cylindrical body 152, above a side end portion of the cylindrical body 152, etc. The discharge portion 155 discharges the solder paste Pst adhering to the screw 151.

[0035] The torque sensor 153 detects the torque of the screw 151. For example, the torque sensor 153 detects the force that the screw 151 receives from the solder paste Pst introduced inside the cylindrical body 152 as torque.

[0036] Although not shown, the viscometer 15 also includes a motor 15M (see FIG. 8A) that rotates the screw 151 and the cylindrical body 152 relatively. For example, the cylindrical body 152 is rotated around the Z axis (with the extension direction of the screw 151 as the axis) relative to the non-rotating screw 151. Note that the motor 15M may be provided outside the viscometer 15 in the printing device 1.

[0037] When the viscosity of the solder paste Pst is measured by the viscometer 15, the control device 17 moves the print head 13 by the head moving mechanism 14 to position the viscometer 15 above the solder paste Pst. Then, the control device 17 operates the viscometer moving unit 16 to extend the viscometer 15 downward, and brings a part of the cylindrical body 152 into contact with the solder paste Pst (state A in Figs. 5 and 6). When a part of the cylindrical body 152 is brought into contact with the solder paste Pst, the control device 17 rotates the cylindrical body 152 by the motor 15M. The solder paste Pst on the mask 11 is introduced (sucked) into the cylindrical body 152 from the introduction portion 154 of the cylindrical body 152 in accordance with the rotation of the cylindrical body 152, and proceeds upward (towards the positive Z direction) along the screw 151 (state B in Fig. 6). Then, when the solder paste Pst that has progressed upward reaches the discharge portion 155 of the cylindrical body 152, it is discharged from the discharge portion 155 to the outside of the cylindrical body 152 (state C in FIG. 6).

[0038] There is a possibility that the solder paste Pst from the previous measurement remains inside the cylindrical body 152. This is because the viscometer 15 introduces the solder paste Pst into the cylindrical body 152 to measure the viscosity of the solder paste Pst. Therefore, in state A and state B of FIG. 6, the solder paste Pst from the previous measurement remains inside the cylindrical body 152, and the torque sensor 153 can detect the force that the screw 151 receives from the remaining solder paste Pst as a torque. On the other hand, in state C of FIG. 6, the solder paste Pst from the previous measurement remaining inside the cylindrical body 152 is all discharged. Therefore, when measuring the solder paste Pst (current measurement), the viscometer 15 waits for the time (reference time T1) required to discharge the solder paste Pst from the previous measurement, thereby creating a state in which the solder paste Pst from the previous measurement is not included and only the solder paste Pst from the current measurement is included. Details of the reference time T1 will be described later.

[0039] The viscometer 15 starts detecting the torque (torque value) by the torque sensor 153 after a reference time T1 has elapsed from the start of measurement of the viscosity, etc. of the solder paste Pst (i.e., the start of rotation of the motor 15M). That is, the screw 151 receives a force (resistance) corresponding to the viscosity from the solder paste Pst while the cylindrical body 152 is rotated by the motor 15M. Thus, the force received by the screw 151 is detected as torque by the torque sensor 153. The control device 17 obtains data (e.g., a torque value) related to the torque of the screw 151 from the torque sensor 153, and measures (e.g., calculates) the viscosity, etc. of the solder paste Pst based on this data. For example, the relationship between the torque value and the viscosity, etc. is information that is known in advance, and the control device 17 may store information on this relationship in a table.

[0040] In this way, the viscometer 15 takes in the solder paste Pst to be measured inside the viscometer 15 and measures the viscosity, etc. The viscometer 15 is, for example, a spiral viscometer. The viscometer 15 has a structure in which the cylindrical body 152 rotates as a rotating body, and the solder paste Pst is taken into the viscometer 15 from the introduction part 154 of the cylindrical body 152, then proceeds upward through the spiral groove formed by the screw 151, and is finally discharged from the discharge part 155 of the cylindrical body 152. The torque generated by the rotation of the cylindrical body 152 is applied to the screw 151 (shaft) having a spiral structure via the solder paste Pst, and the torque applied to the screw 151 changes depending on the viscosity of the solder paste Pst. As a result, the printing device 1 can measure the viscosity, etc. of the solder paste Pst using the viscometer 15. At this time, the torque applied to the screw 151 changes depending on the amount of solder paste Pst, so for example, the measurement is performed in a state where the screw 151 having a helical structure is completely filled with the solder paste Pst.

[0041] Here, the viscometer 15 is exemplified as a viscometer in which the screw 151 does not rotate and the cylindrical body 152 rotates around the screw 151, but is not limited thereto. For example, the viscometer 15 may be a viscometer in which the screw 151 rotates and the cylindrical body 152 does not rotate. That is, the viscometer 15 may be a viscometer in which the screw 151 rotates around the axis in the direction in which the screw 151 extends (Z direction), the cylindrical body 152 surrounds the periphery of the screw 151, and the cylindrical body 152 itself does not rotate. In this case, the torque sensor 153 may detect the force (reaction force) that the screw 151 receives from the solder paste Pst introduced inside the cylindrical body 152 as torque.

[0042] FIG. 7 is a diagram showing an example of a position where a viscometer 15 is placed with respect to the solder paste Pst when measuring the viscosity and the like of the solder paste Pst.

[0043] The squeegee 32 extends linearly along the X direction. The solder paste Pst is repeatedly scraped on the mask 11 by the squeegee 32. Therefore, the solder paste Pst is present on the mask 11 in a shape elongated in the X direction. When measuring the viscosity, etc. using the viscometer 15, the viscometer 15 is arranged so as to contact the solder paste Pst from above. In this case, the viscometer 15 is arranged so as to contact a portion Ar2 of the solder paste Pst elongated in the X direction, which avoids the central portion Ar1 and the end portion Ar3 in the X direction. The central portion Ar1 is a portion whose position in the X direction overlaps with the pattern region 11A of the mask 11. This is because the amount of the solder paste Pst may be less at the end portion Ar3 than at other positions of the solder paste Pst other than the end portion Ar3, and the amount of the solder paste Pst for measuring the viscosity, etc. may be insufficient. In addition, the shape of the central portion Ar1, which has been adjusted by the squeegee 32, is destroyed when the central portion Ar1 is used to measure the viscosity and other properties of the solder paste Pst. If the destroyed portion passes through the opening pattern 11K in the subsequent screen printing, the amount of solder paste Pst filling the opening pattern 11K may be insufficient, resulting in defective printing. For this reason, it is preferable to measure the viscosity and other properties of the solder paste Pst in the portion Ar2, which avoids the central portion Ar1 and the end portion Ar3. The viscometer 15 can be moved along the longitudinal direction of the solder paste Pst by driving the X-direction moving mechanism 16c.

[0044] 7, the pattern region 11A of the mask 11 is formed in the center of the mask 11, but this is not limited thereto. That is, the pattern region 11A of the mask 11 may be located at a position shifted from the center of the mask 11. In this case, the position of the solder paste in the X direction that overlaps with the pattern region 11A of the mask 11 is a position shifted from the center Ar1. In this case, the control device 17 measures the viscosity, etc. of the solder paste Pst at a position that avoids the position of the solder paste in the X direction that overlaps with the pattern region 11A of the mask 11 and the end portion Ar3.

[0045] The printer 1 may change the printing conditions based on the measurement results of the viscosity of the solder paste Pst, etc. This allows the printer 1 to continue printing stably even if the solder paste Pst on the mask 11 changes over time and the viscosity changes.

[0046] FIG. 8A is a block diagram showing an example of the configuration of a control system in the printing device 1.

[0047] The control device 17 included in the printing device 1 controls the operation of the lift cylinder 22, the head moving mechanism 14, the attack angle change unit 33, and the viscometer moving unit 16. The control device 17 operates the lift cylinder 22 to selectively raise and lower one of the pair of squeegee units 23 (i.e., one of the two squeegees 32) relative to the base unit 21. The control device 17 operates the head moving mechanism 14 to move the print head 13 in the Y direction. The control device 17 operates the attack angle change unit 33 to change the attack angle θ of the squeegee 32. The control device 17 operates the viscometer moving unit 16 to move the viscometer 15 in the up and down directions and the X direction relative to the base unit 21 of the print head 13.

[0048] In addition, the control device 17 is connected to a viscometer 15, a thermometer 18, a temperature regulator 19, and a touch panel TP.

[0049] The viscometer 15 detects detection information corresponding to the viscosity of the solder paste Pst (for example, data related to the torque of the screw 151). The control device 17 receives the detection information (for example, a torque value) of the viscosity of the solder paste Pst measured by the viscometer 15.

[0050] The thermometer 18 is installed, for example, at a position inside the printer 1 and measures the temperature inside the printer 1 (the work space where printing is performed). The temperature regulator 19 maintains, increases, or decreases the temperature inside the printer 1.

[0051] As shown in FIG. 6, the control device 17 includes a storage unit 61, a print control unit 62, a timer 63, a measurement unit 64, a print condition change unit 66, and a temperature control unit 67.

[0052] The storage unit 61 stores at least an operation program 61a that defines the procedure of the printing operation executed by the print head 13, and printing condition data 61b that is data of printing conditions related to the print head 13. The printing condition data 61b includes mutual relationship data such as the viscosity of the solder paste Pst that optimizes the printing state, the attack angle θ, the pressing force of the squeegee 32, the moving speed of the squeegee 32, and the speed at which the mask 11 and the substrate KB are separated. The storage unit 61 may hold a reference time T1. The storage unit 61 may also hold a reference time T1 for each type of solder paste Pst. Information on the reference time T1 for each type of solder paste Pst may be held in, for example, a table format. The storage unit 61 may hold a cleaning notification time T2 to be described later and a limit time T3 to be described later. The storage unit 61 may also hold a cleaning notification time T2 and a limit time T3 for each type of solder paste Pst. The information on the cleaning notification time T2 and the limit time T3 for each type of solder paste Pst may be stored in, for example, a table format. The cleaning notification time T2 will be described in detail later.

[0053] The print control unit 62 executes the operation program 61a under the printing conditions selected from the printing condition data 61b, and operates the lift cylinder 22 and the head moving mechanism 14 to perform the printing operation.

[0054] The timer 63 measures a predetermined time. The timer 63 is used, for example, to determine whether a reference time T1 has elapsed, whether a cleaning notification time T2 has elapsed, whether a limit time T3 has elapsed, and the like. The timer 63 includes a viscometer stop timer N1 and a solder replacement timer N2. The viscometer stop timer N1 is used to measure the time that has elapsed since the previous measurement of the viscosity, etc., of the solder paste Pst. The solder replacement timer N2 is used to measure the time that has elapsed since the introduction of the solder paste Pst into the viscometer 15 was started.

[0055] The measurement unit 64 uses the viscometer 15 to measure the viscosity, etc., of the solder paste Pst on the mask 11. For example, the measurement unit 64 obtains data (e.g., a torque value) related to the torque of the screw 151 from the torque sensor 153 when the cylindrical body 152 of the viscometer 15 rotates, and derives (e.g., calculates) the viscosity, etc., of the solder paste Pst based on this data. For example, information on the relationship between the torque value and the viscosity, etc. may be stored in advance in the storage unit 61, and the measurement unit 64 may derive the viscosity, etc., of the solder paste Pst based on the information on this relationship and the data related to the torque.

[0056] The measurement control unit 65 controls the motor 15M and the measurement unit 64 to execute a viscosity measurement process. The viscosity measurement process is a process of measuring the viscosity, etc., of the solder paste Pst on the mask 11 using the viscometer 15. The viscosity measurement process will be described in detail later. For example, the measurement control unit 65 causes the measurement unit 64 to derive the viscosity, etc., after a reference time T1 has elapsed since the motor 15M was rotated.

[0057] The measurement control unit 65 also manages the state of the viscometer 15. The state management of the viscometer 15 is performed, for example, in parallel with the viscosity measurement process. The measurement control unit 65 uses a viscometer stop timer N1 to control the viscosity and other properties of the solder paste Pst inside the viscometer 15 so as not to deteriorate. The measurement control unit 65 performs a solder paste replacement process, a process to stop operation of the printing device 1, and a cleaning warning process according to the time measured by the viscometer stop timer N1.

[0058] The solder paste replacement process is a process of introducing the solder paste Pst accumulated on the mask 11 and discharging the solder paste Pst remaining inside the viscometer 15, thereby replacing the solder paste Pst remaining inside the viscometer 15 with the solder paste Pst accumulated on the mask 11. The operation stop process is a process of stopping the operation (i.e., printing) of the printing device 1. The cleaning warning process is a process of warning the operator to clean the viscometer 15. In this case, the measurement control unit 65 may display cleaning warning information warning the operator to clean via the touch panel TP. Note that the cleaning warning information may be presented by a method other than displaying the warning information (for example, sound output).

[0059] The measurement control unit 65 continues normal printing operation when the time measured by the viscometer stop timer N1 is equal to or shorter than the predetermined cleaning notification time T2. The measurement control unit 65 performs solder paste replacement processing when the time measured by the viscometer stop timer N1 is longer than the cleaning notification time T2 and equal to or shorter than the predetermined limit time T3. The measurement control unit 65 performs operation stop processing and cleaning warning processing when the time measured by the viscometer stop timer N1 is longer than the limit time T3.

[0060] The cleaning notification time T2 is a time for determining whether or not to notify an operator or the like to clean the viscometer 15. This notification (cleaning notification) is less urgent than a cleaning warning. The cleaning notification time T2 is a time during which the viscosity, etc. of the solder paste Pst does not exceed a predetermined range, that is, the time during which it is within a predetermined range. The cleaning notification time T2 may be, for example, a time (for example, about one hour) that does not cause the solder paste Pst to deteriorate. For example, due to a change in time measurement, the components contained in the solder paste Pst in the viscometer 15 may evaporate or the antioxidant may oxidize, which may cause the solder paste Pst to deteriorate and increase in viscosity, etc. The deterioration here refers to, for example, deterioration to the extent that printing is hindered, and deterioration that makes printing through the mask 11 difficult. For example, deterioration to the extent that the solder paste Pst solidifies and becomes a lump.

[0061] The limit time T3 is the limit time during which the viscosity, etc., of the solder paste Pst does not exceed a predetermined range. The limit time T3 can also be said to be the limit time during which the viscosity of the solder paste Pst in the viscometer 15 remains at a viscosity that allows printing to be performed by the printer 1. The limit time T3 is longer than the cleaning notification time T2.

[0062] The printing condition changing unit 66 changes the printing conditions related to the print head 13 as necessary based on the viscosity of the solder paste Pst measured by the viscosity measuring unit 70. The printing condition changing unit 66 changes the printing conditions, for example, by changing at least one of the attack angle θ, the pressing force of the squeegee 32, the movement speed of the squeegee 32, and the speed at which the mask 11 is separated from the substrate KB.

[0063] The temperature control unit 67 acquires information on the temperature inside the printing device 1 from the thermometer 18. For example, the temperature control unit 67 instructs the temperature regulator 19 to make the temperature inside the printing device 1 a predetermined temperature, or instructs the temperature regulator 19 to change (increase or decrease) the temperature inside the printing device 1 by a predetermined temperature. The temperature control unit 67 controls the temperature inside the printing device 1 together with the thermometer 18 and the temperature regulator 19 as necessary based on the viscosity of the solder paste Pst measured by the viscosity measurement unit 70. For example, the temperature control unit 67 may control the temperature inside the printing device 1 to increase when the viscosity of the measured solder paste Pst is increased compared to the previous measurement, or when this viscosity is greater than a predetermined threshold value. For example, the temperature control unit 67 may control the temperature inside the printing device 1 to decrease when the viscosity of the measured solder paste Pst is decreased compared to the previous measurement, or when this viscosity is less than a predetermined threshold value.

[0064] The touch panel TP has a function as an operation unit that receives various operations from an operator, and a function as a display unit that displays various display data. For example, the touch panel TP displays error information when the viscosity of the measured solder paste exceeds an expected range.

[0065] Furthermore, the touch panel TP may display cleaning recommendation information recommending cleaning of the viscometer 15, for example, if the viscosity of the solder paste Pst has not been measured within a cleaning notification time T2 since the previous measurement of the viscosity of the solder paste Pst. The touch panel TP may display cleaning warning information warning the user to clean the viscometer 15, for example, if the viscosity of the solder paste Pst has not been measured within a limit time T3 since the previous measurement of the viscosity of the solder paste Pst. The cleaning warning information is information that is more urgent or important than the cleaning recommendation information. For example, the cleaning warning information may be presented as a message or other information in a more noticeable form than the cleaning recommendation information.

[0066] Instead of the touch panel TP, an operation unit and a display unit may be provided separately in the printing device 1. Also, a speaker may be provided in the printing device 1 together with the touch panel TP. In this case, the speaker may output various information by sound. The display of information and the output by sound here are examples of transmitting or presenting information.

[0067] Next, the reference time T1 will be described in detail. The reference time T1 is the time required to replace the solder paste Pst inside the cylindrical body 152. That is, the reference time T1 is the time required to replace the solder paste Pst inside the cylindrical body 152 from the timing when the motor 15M that rotates the cylindrical body 152 to suck the solder paste Pst from the introduction part 154 of the cylindrical body 152 is started until the solder paste Pst is discharged from the discharge part 155 of the cylindrical body 152 (hereinafter referred to as the discharge time). The reference time T1 is set to a time longer than the discharge time, taking into consideration that the old solder paste Pst remaining inside the cylindrical body 152, that is, the solder paste Pst that was sucked into the cylindrical body 152 during the previous measurement and remains inside the cylindrical body 152, is replaced with new solder paste Pst. The measurement control unit 65 causes the measurement unit 64 to derive the viscosity, etc., after the reference time T1 has elapsed when the solder paste Pst to be measured is reliably filled inside the cylindrical body 152, so that the physical property values ​​of the solder paste Pst on the mask 11 with high reliability, such as the viscosity, can be measured. The reference time T1 is stored in the storage unit 61.

[0068] The reference time T1 may be determined based on a discharge time measured after replacing or cleaning the cylindrical body 152 or the screw 151. Alternatively, the reference time T1 may be a reference time T1 used in another viscometer having the same shape or structure as the viscometer 15. The reference time T1 is set by the measurement control unit 65, for example.

[0069] Furthermore, the reference time T1 may differ depending on the type of solder paste Pst. This is because the viscosity differs depending on the type of solder paste Pst, and the time it takes for the solder paste Pst to pass through the viscometer 15 may also differ. The storage unit 61 may store information on the reference time T1 for each type of solder paste Pst. For example, by the storage unit 61 storing information on the reference time T1 in advance, measurement to derive the reference time T1 is not required.

[0070] For example, the measurement control unit 65 may specify the type of solder paste Pst to be used for printing via the touch panel TP, obtain information on the reference time T1 corresponding to this type of solder paste Pst, and set the reference time T1. If the information on the reference time T1 for the specified type of solder paste Pst is not stored in the storage unit 61, the reference time T1 corresponding to this type of solder paste Pst may be measured and stored in the storage unit 61 when the viscosity, etc. of this type of solder paste Pst is measured for the first time. This allows the printing device 1 to use the stored information on the reference time T1 from the next time the viscosity, etc. of this type of solder paste Pst is measured.

[0071] Also, for example, the measurement control unit 65 may specify the type of solder paste Pst used for printing via the touch panel TP, obtain information on the cleaning notification time T2 and the limit time T3 corresponding to this type of solder paste Pst, and set the cleaning notification time T2 and the limit time T3. The information on the cleaning notification time T2 and the limit time T3 for the specified type of solder paste Pst is held in the memory unit 61.

[0072] FIG. 8B is a diagram showing an example of a table TB1 that holds information about the reference time T1.

[0073] Table TB1 holds information on the reference time T1 for each type of solder paste Pst. In addition to the type of solder paste Pst and the reference time T1, table TB1 may hold information on the number of rotations (or the number of rotations per unit time) (also simply referred to as the number of rotations) of the cylindrical body 152 of the viscometer 15 during viscosity measurement and the temperature inside the printing device 1. In other words, the reference time T1 may be determined according to the type of solder paste Pst and at least one of the number of rotations of the cylindrical body 152 and the temperature inside the printing device 1. In other words, the reference time T1 may be determined according to the type of solder paste Pst, the type of viscometer 15, and the environment inside the printing device 1.

[0074] The rotation speed of the cylindrical body 152 is detected by, for example, a rotation sensor (not shown) provided in the viscometer 15, and is sent from the viscometer 15 to the measurement control unit 65. The higher the rotation speed of the cylindrical body 152, the faster the speed of the solder paste Pst advancing upward in the cylindrical body 152, and the lower the rotation speed of the cylindrical body 152, the slower the speed of the solder paste Pst advancing upward in the cylindrical body 152. Therefore, it is presumed that the higher the rotation speed, the faster the replacement speed of the solder paste Pst in the cylindrical body 152. Similarly, the higher the temperature in the printing device 1, the lower the viscosity of the solder paste Pst is likely to be, and the faster the speed of the solder paste Pst advancing upward in the cylindrical body 152 is. The lower the temperature in the printing device 1, the higher the viscosity of the solder paste Pst is likely to be, and the slower the speed of the solder paste Pst advancing upward in the cylindrical body 152 is. Therefore, it is presumed that the higher the temperature, the faster the replacement speed of the solder paste Pst inside the cylindrical body 152.

[0075] FIG. 8C is a diagram showing an example of a table TB2 that holds information about the cleaning notification time T2.

[0076] Table TB2 holds information on the cleaning notification time T2 for each type of solder paste Pst. Furthermore, table TB2 may hold information on the temperature inside the printing device 1 in addition to the type of solder paste Pst and the cleaning notification time T2. That is, the cleaning notification time T2 may be determined according to the type of solder paste Pst and the temperature inside the printing device 1. That is, the cleaning notification time T2 may be determined according to the type of solder paste Pst and the environment inside the printing device 1.

[0077] It is presumed that the higher the temperature inside the printer 1, the lower the viscosity of the solder paste Pst and the slower the rate at which the solder paste Pst changes. It is presumed that the lower the temperature inside the printer 1, the higher the viscosity of the solder paste Pst and the faster the rate at which the solder paste Pst changes.

[0078] Although the explanation of the table that holds information on the limit time T3 is omitted, it is similar to the table related to the cleaning notification time T2.

[0079] Next, the operation of the printing device 1 will be described with reference to a flowchart. FIG. 9 is a flowchart showing an example of the operation of the printing device 1.

[0080] The control device 17 waits while monitoring the introduction of the substrate KB from the upstream side of the printing device 1 (S11), and determines whether or not the substrate KB has been detected by a sensor (not shown) (S12). If the substrate KB is not detected in step S12, the process proceeds to step S11. If the substrate KB is detected in step S12, a substrate transport mechanism (not shown) introduces the substrate KB from the upstream side (S13), and the substrate support unit 12 supports the substrate KB. The printing control unit 62 performs a printing preparation operation (S14).

[0081] The measurement control unit 65 judges whether or not it is necessary to measure the viscosity of the solder paste Pst (S15). For example, when printing of a predetermined number of boards KB is completed, it may be judged that it is necessary to measure the viscosity. Also, when a predetermined time has passed since the operation start time of the printer 1 (for example, the printing start time), it may be judged that it is necessary to measure the viscosity. Also, when a predetermined time has passed since the previous viscosity measurement time, that is, when the measurement time by the viscometer stop timer N1 reaches a predetermined time, it may be judged that it is necessary to measure the viscosity. Also, when the current time measured by the timer 63 becomes the time to measure the viscosity, etc., as determined by a predetermined schedule, it may be judged that it is necessary to measure the viscosity.

[0082] If it is necessary to measure the viscosity or the like, the viscosity measuring unit 70 performs a viscosity measurement process (S16).

[0083] If it is not necessary to measure viscosity or the like in step S15, or after the processing of step S16, the print control unit 62 performs a print operation (S17). The print control unit 62 performs a plate separation operation (S18). A substrate transport mechanism (not shown) carries out the substrate KB after the printing operation is completed (S19).

[0084] The printing control unit 62 determines whether or not the production (i.e., printing) of the predetermined number of boards KB has been completed (S20). If the production of the predetermined number of boards KB has not been completed, the process proceeds to step S11. If the production of the predetermined number of boards KB has been completed, the process of FIG. 9 ends.

[0085] According to the process of FIG. 9, the printer 1 can measure the viscosity and other properties of the solder paste Pst at a predetermined timing while printing the solder paste Pst on the board KB.

[0086] FIG. 10 is a flowchart showing an example of the viscosity measurement process.

[0087] The head moving mechanism 14 moves the viscometer 15 to a measurement position under the control of the control device 17 (S21). The measurement position here is a position where the viscometer 15 moves in the X direction and descends to contact the solder paste Pst as necessary. The measurement control unit 65 starts driving the viscometer 15 (S22). In this case, the measurement control unit 65 starts driving the motor 15M, and rotates one of the screw 151 and the cylindrical body 152 with the screw 151 in contact with the solder paste Pst. When the drive of the viscometer 15 starts, the measurement control unit 65 resets the value of the solder replacement timer N2 (sets it to a value of 0) and starts time measurement by the solder replacement timer N2. The measurement control unit 65 determines whether the time measured by the solder replacement timer N2 has passed the reference time T1 (S23). If the time measured by the solder replacement timer N2 has not passed the reference time T1 (No in step S23), the process of step S23 is repeated.

[0088] If the time measured by the solder replacement timer N2 has exceeded the reference time T1 in step S23 (Yes in step S23), the measurement unit 64 measures the viscosity and other properties of the solder paste Pst introduced into the viscometer 15 (S24).

[0089] The measurement control unit 65 stops driving the viscometer 15 (S25). In this case, the measurement control unit 65 stops driving the motor 15M and ends the rotation of one of the screw 151 and the cylindrical body 152. When the driving of the viscometer 15 is stopped, the solder replacement timer N2 ends the time measurement. The measurement control unit 65 resets the value of the viscometer stop timer N1 (to a value of 0) (S26) and starts the time measurement by the viscometer stop timer N1.

[0090] The head moving mechanism 14 moves the viscometer 15 to a standby position under the control of the control device 17 (S27). The standby position here is a predetermined position where the viscometer 15 is located during a period when the viscosity, etc. of the solder paste Pst is not being measured. The printing condition changing unit 66 may change the printing conditions based on the measured viscosity, etc. (S28). The measurement control unit 65 may also notify an abnormality via the touch panel TP (S28). The abnormality notification here may include displaying error information indicating that the measured viscosity, etc. is a value that exceeds a predetermined range (normal range). The abnormality notification may be presented by a method other than a display (for example, sound output).

[0091] 10, the printing device 1 waits for a reference time T1 from the time the viscometer 15 is driven, and thereby can complete the replacement of the solder paste Pst remaining in the viscometer 15 with the solder paste Pst newly introduced from above the mask 11. Therefore, the solder paste Pst remaining in the viscometer 15 and the newly introduced solder paste Pst do not mix, and therefore it is possible to obtain highly reliable measured values ​​of viscosity, etc.

[0092] Fig. 11 is a flowchart showing an example of an operation related to viscometer state management. Viscometer state management refers to managing various states related to the viscometer 15. The process of Fig. 11 may be executed in parallel with the process of Fig. 9.

[0093] The measurement control unit 65 determines whether the time measured by the viscometer stop timer N1 is longer than the cleaning notification time T2 (also referred to as N1>T2) (S31). If the time measured by the viscometer stop timer N1 is not longer than the cleaning notification time T2 (No in step S31), the measurement control unit 65 proceeds to step S31.

[0094] In other words, if the time measured by the viscometer stop timer N1 is not longer than the cleaning notification time T2 (No in step S31), it indicates that the time elapsed since the previous measurement of the viscosity, etc. of the solder paste Pst is shorter than the cleaning notification time T2, and that the viscosity, etc. of the solder paste Pst are being measured at intervals that do not cause deterioration of the solder paste Pst. In this case, cleaning of the viscometer 15 is not necessary, and the print control unit 62 continues to execute the printing operation.

[0095] If the time measured by the viscometer stop timer N1 is longer than the cleaning notification time T2 (Yes in step S31), the measurement control unit 65 determines whether the time measured by the viscometer stop timer N1 is longer than the limit time T3 (also written as N1>T3) (S32).

[0096] If the time measured by the viscometer stop timer N1 is not longer than the limit time T3 (No in step S32), the measurement control unit 65 performs a solder paste replacement process (S33).

[0097] That is, in step S33, since the cleaning notification time T2 has passed since the previous measurement of the viscosity, etc. of the solder paste Pst, there is a possibility that the solder paste Pst may deteriorate thereafter, so the measurement control unit 65 performs a solder paste replacement process. Note that, as will be described later, the solder paste replacement process also serves as a measurement of the viscosity, etc. of the next solder paste Pst.

[0098] If the time measured by the viscometer stop timer N1 is longer than the limit time T3 (Yes in step S32), the measurement control unit 65 performs operation stop processing and cleaning warning processing (S34).

[0099] In this way, before the cleaning notification time T2 has elapsed since the previous measurement of the viscosity, etc., of the solder paste Pst, there is a sufficient time until the solder paste Pst changes in the viscometer 15. Therefore, the printing device 1 can continue normal printing operations. Also, if the cleaning notification time T2 has elapsed since the previous measurement of the viscosity, etc., of the solder paste Pst, there is a possibility that the solder paste Pst will change in the viscometer 15 after this. In response to this, the printing device 1 can discharge the solder paste Pst remaining in the viscometer 15 to the outside by performing the solder paste replacement process. Therefore, a highly reliable measurement value can be obtained using new solder paste Pst. Also, if the limit time T3 has elapsed since the previous measurement of the viscosity, etc., of the solder paste Pst, there is a high possibility that the solder paste Pst will change in the viscometer 15 after this. In response to this, the printing device 1 does not perform the solder paste replacement process and stops printing by the printing device 1, thereby preventing failure of the viscometer 15 and failure of other equipment in the printing device 1. In addition, at this time, the printing device 1 can notify the user that cleaning of the viscometer 15 is highly urgent by executing a cleaning warning process.

[0100] FIG. 12 is a flowchart showing an example of the solder paste replacement process.

[0101] The measurement control unit 65 determines whether or not the solder paste replacement process is possible (S41). For example, if the components used in the solder paste replacement process (e.g., mask 11, viscometer 15) are installed in predetermined positions within the printing device 1, it is determined that the solder paste replacement process is possible. On the other hand, if the components used in the solder paste replacement process are not installed in predetermined positions within the printing device 1 (e.g., removed), it is determined that the solder paste replacement process is not possible.

[0102] If the solder paste replacement process is possible (Yes in step S41), the printing device 1 performs the processes of steps S22 to S27 shown in Fig. 10. Note that, here, the printing device 1 does not perform the process of step S28.

[0103] If the solder paste replacement process is not possible (No in step S41), the measurement control unit 65 issues a viscometer cleaning notification via the touch panel TP (S42). The viscometer cleaning notification is to notify cleaning recommendation information that recommends cleaning of the viscometer 15. The cleaning recommendation information may be presented by a method other than display (e.g., sound output). The measurement control unit 65 notifies the cleaning recommendation information, for example, to a person as an operator, or to a robot device.

[0104] Therefore, for example, by checking the cleaning recommendation information, an operator can remove at least a part of the viscometer 15 (for example, the cylindrical body 152) from the printing apparatus 1 and clean it.

[0105] 12, the printer 1 can replace the solder paste Pst remaining in the viscometer 15 from before the previous measurement with new solder paste Pst, thereby preventing the solder paste Pst from solidifying in the viscometer 15. This allows for highly reliable measured values ​​of viscosity, etc. to be obtained. In addition, when replacing the solder paste Pst, the viscosity, etc. of the newly introduced solder paste Pst can also be measured, resulting in high measurement efficiency.

[0106] 9 to 12, the printer 1 starts the viscosity measurement process (step S16 in FIG. 9, steps S21 to S28 in FIG. 10) in a state in which the solder paste Pst from the previous measurement remains inside the viscometer 15. In the operation of the viscosity measurement process itself, the printer 1 pushes out the solder paste Pst from the previous measurement target to the outside of the viscometer 15 by the solder paste Pst to be measured this time.

[0107] After the start of the viscosity measurement process and a sufficient time (reference time T1) has elapsed for the solder paste Pst inside the viscometer 15 to be replaced, the printing device 1 calculates the viscosity, etc. of the solder paste Pst by using the value (torque value) output from the viscometer 15.

[0108] In the case of a spiral viscometer, for example, the solder paste Pst advances in one direction from the inlet 154 to the outlet 155, and a highly viscous liquid (for example, solder paste Pst) that is pushed upward is the measurement target. Therefore, the solder paste Pst of the current measurement target taken into the viscometer 15 fills the inside of the viscometer 15 (cylindrical body 152). As the solder paste Pst of the current measurement target fills, the solder paste Pst of the previous measurement target can be pushed out of the viscometer 15.

[0109] For example, the printing device 1 measures the time from when the introduction of the solder paste Pst is started from the introduction part 154 of the viscometer 15 to when the discharge part 155 of the viscometer 15 starts discharging the solder paste Pst, as the reference time T1, when the viscometer 15 has been cleaned. That is, the reference time T1 is, for example, the time when the viscometer 15 is filled with a necessary amount of solder paste Pst at the time of the first measurement of viscosity, etc. by the printing device 1, until the viscosity, etc. of the solder paste Pst in the viscometer 15 becomes a constant value and the value of the viscosity, etc. of the solder paste Pst being measured is set. This reference time T1 is equal to the replacement time of the solder paste Pst in the viscometer 15. Therefore, the printing device 1 measures the solder paste Pst after the reference time T1 has elapsed from the start of the viscosity measurement process (for example, the start of driving the viscometer 15 in step S22 of FIG. 10), thereby ensuring the replacement of the liquid to be measured, which is difficult to observe, and making it possible to measure the viscosity, etc. of the liquid to be measured this time.

[0110] Furthermore, the printing device 1 periodically measures the viscosity and the like when the cleaning notification time T2 has elapsed since the previous measurement, thereby suppressing deterioration of the solder paste Pst attached to the viscometer 15. Furthermore, when the cleaning notification time T2 or more has elapsed since the previous measurement of the viscosity and the like, the printing device 1 presents information (e.g., cleaning recommendation information) encouraging cleaning of the viscometer 15, and notifies the operator that cleaning of the viscometer 15 is necessary (step S33 in FIG. 11, step S42 in FIG. 12). This presentation may include, for example, at least one of audio output from a speaker and screen display on the touch panel TP. This presentation may be presented to the operator. The operator can prevent the liquid attached to the viscometer 15 from deteriorating by checking the cleaning recommendation information and cleaning the viscometer 15.

[0111] In this way, according to the printing device 1 of the present embodiment, the viscosity and the like of the solder paste Pst can be measured periodically inside the printing device 1. At this time, the printing device 1 replaces the solder paste Pst inside the viscometer 15 (inside the cylindrical body 152) by pushing out the old solder paste Pst from the previous or previous measurement object remaining inside the viscometer 15 with the new solder paste Pst to be measured this time. The printing device 1 can derive the viscosity and the like of the solder paste Pst to be measured this time by using the detection value (torque value) for the replaced solder paste Pst. Note that the solder paste Pst is one example of the measurement object, and other liquids may also be the measurement object.

[0112] Furthermore, according to the printing device 1 of this embodiment, the viscosity, etc. of the solder paste Pst is measured when a cleaning notification time T2 has elapsed after the previous measurement of viscosity, etc., which is shorter than the time when the solder paste Pst attached to the viscometer 15 deteriorates. This allows the printing device 1 to suppress deterioration of the solder paste Pst attached to the viscometer 15. At this time, the printing device 1 also transmits cleaning recommendation information. This transmission is, for example, a presentation to a person, and may include at least one of audio output by the speaker SP and screen display by the touch panel TP. Furthermore, the transmission may include, for example, sending instruction information to encourage the robot to clean.

[0113] Furthermore, when the limit time T3 has elapsed since the previous measurement, printing is stopped to prevent breakdowns in the viscometer 15 and other equipment in the printing device 1. At this time, the printing device 1 can also notify the operator or the like of the urgency of cleaning by transmitting cleaning warning information.

[0114] Furthermore, the printing device 1 does not have a cleaning unit that automatically cleans the inside of the viscometer 15, but periodically measures the viscosity and other properties of the solder paste Pst before it deteriorates, and presents cleaning recommendation information. This makes it possible to suppress increases in the device cost of the printing device 1 and decreases in the operating rate during cleaning. When the viscosity and other properties are measured periodically, the inside of the viscometer 15 is renewed, and the old solder paste Pst is discharged to the outside of the viscometer 15, so that a decrease in the measurement accuracy of the viscosity and other properties can be suppressed. If the viscosity and other properties cannot be measured periodically, for example, if the limit time T3 is not observed due to a device downtime such as a break time, the printing device 1 stops the printing operation and presents cleaning warning information. Thus, the operator can recognize the need for cleaning, and by removing and cleaning the viscometer 15, it is possible to suppress a decrease in the quality of the measurement target and a breakdown of the viscometer 15. In addition, a viscometer cleaning notification (step S42 in FIG. 12) can be issued according to the time elapsed since the previous viscosity and other properties were measured, and then a cleaning warning process (step S34 in FIG. 11) can be executed. In other words, the printing device 1 can provide information regarding cleaning of the viscometer 15 in stages.

[0115] Therefore, the printing device 1 can suppress deterioration in the quality of the solder paste Pst to be measured, and can also suppress solidification of the solder paste Pst adhering to the inside of the viscometer 15, thereby suppressing breakdown of the viscometer 15.

[0116] (Outline of the embodiment) As a result, the present disclosure includes at least the following items. Note that in parentheses, examples of components corresponding to the above-described embodiment are given, but the present disclosure is not limited to these.

[0117] [Item 1] A printing device (printing device 1) that prints solder paste (solder paste Pst) on a substrate (substrate KB) through a mask (mask 11) having a predetermined opening pattern (opening pattern 11K), a suction section (viscometer 15) capable of introducing the solder paste on the mask from a suction port (inlet section 154) and discharging the paste from an opening section (discharge section 155); a measuring unit (measuring unit 64) that measures the viscosity or a viscosity equivalent value of the solder paste introduced into the suction unit multiple times; a control unit (measurement control unit 65) that causes the measurement unit to measure the viscosity or the viscosity equivalent value of the solder paste when a first predetermined time (cleaning notification time T2) has elapsed since the previous measurement by the measurement unit; A printing device having the above configuration.

[0118] As a result, when a first predetermined time has elapsed since the previous measurement, the printing device introduces the solder paste to be measured into the suction unit and measures the viscosity, etc. of the solder paste, thereby replacing the solder paste adhering to the inside of the suction unit. Therefore, the printing device can prevent the solder paste that may have adhered to the inside of the suction unit and been altered from mixing with the solder paste to be measured next time, thereby obtaining highly reliable measurement values ​​during the production of circuit boards and preventing a decrease in the measurement accuracy of the solder paste to be measured next time. In this way, the printing device can prevent a decrease in the measurement accuracy of the viscosity, etc., even when measuring the viscosity, etc. of the object to be measured inside the suction unit.

[0119] [Item 2] The predetermined time is a time during which the viscosity or the viscosity equivalent value of the solder paste introduced into the suction section does not exceed a predetermined range. Item 1. The printing device according to item 1.

[0120] This allows the printing device to replace the solder paste adhering to the inside of the suction section before the solder paste adhering to the inside of the suction section deteriorates.

[0121] [Item 3] A transmission unit (touch panel TP) that transmits information (cleaning guide information) that prompts cleaning of the suction unit, The control unit causes the transmitting unit to transmit cleaning recommendation information that recommends cleaning of the suction unit when the first predetermined time has elapsed since the previous measurement by the measurement unit. 4. A printing device according to any one of items 1 to 3.

[0122] This allows the printer 1 to transmit cleaning recommendation information as information encouraging cleaning of the printer before the solder paste adhering to the inside of the suction section deteriorates, allowing the work robot or worker to recognize the need for cleaning and clean the suction section.

[0123] [Item 4] the control unit stops printing by the printing device when a second predetermined time (a limit time T3) longer than the first predetermined time has elapsed since the previous measurement by the measurement unit. 4. A printing device according to any one of items 1 to 3.

[0124] For example, if a part of the suction unit is removed from the printing device or if the printing device is stopped for a long period of time, the solder paste replacement process may not be performed, and the viscosity and other measurements may not be performed until the second predetermined time has elapsed since the previous measurement. In this case, the solder paste in the suction unit is not replaced, and there is a high possibility that the solder paste in the suction unit will subsequently deteriorate. In response to this, the printing device can prevent the suction unit or other equipment in the printing device from breaking down by stopping printing.

[0125] [Item 5] A transmission unit that transmits information to prompt cleaning of the suction unit, The control unit causes the transmitting unit to transmit cleaning warning information that warns the user to clean the suction unit when the second predetermined time has elapsed since the previous measurement by the measurement unit. 5. The printing device according to item 4.

[0126] This allows the printing device to issue cleaning warning information as information encouraging cleaning of the printing device, thereby enabling the work robot or worker to recognize the urgent need for cleaning and to quickly clean the suction unit.

[0127] [Item 6] The transmission of the information includes at least one of audible output and screen display of the information to the worker. Item 6. A printing device according to item 3 or 5.

[0128] This allows the operator to recognize the need for manual cleaning and to manually clean the suction portion.

[0129] [Item 7] A viscosity measurement method for measuring the viscosity of a solder paste printed on a substrate through a mask having a predetermined opening pattern using a suction unit, comprising: the suction unit is capable of introducing the solder paste on the mask through a suction port and discharging it through an opening, an introduction step of introducing the solder paste on the mask into the inside of the suction portion; a measuring step of measuring the viscosity or a viscosity equivalent value of the solder paste introduced into the suction portion a plurality of times; a control step of measuring the viscosity or the viscosity equivalent value of the solder paste in the measuring step when a first predetermined time has elapsed since the previous measurement in the measuring step; The viscosity measuring method according to claim 1,

[0130] As a result, the viscosity measurement method can achieve the same effect as item 1.

[0131] [Item 8] The predetermined time is a time during which the viscosity or the viscosity equivalent value of the solder paste introduced into the suction section does not exceed a predetermined range. Item 7. The viscosity measuring method according to item 7.

[0132] As a result, the viscosity measurement method can achieve the same effect as item 2.

[0133] [Item 9] The method further includes a step of transmitting information to prompt the user to clean the suction unit. The control step includes a step of transmitting, in the transmitting step, cleaning recommendation information that recommends cleaning of the suction unit when the first predetermined time has elapsed since the previous measurement in the measuring step. Item 9. The viscosity measurement method according to any one of items 6 to 8.

[0134] As a result, the viscosity measurement method can obtain the same effect as item 3.

[0135] [Item 10] the control step includes a step of stopping printing by the printing device having the suction unit when a second predetermined time longer than the first predetermined time has elapsed since the previous measurement by the measurement step. The viscosity measuring method according to any one of claims 6 to 9.

[0136] As a result, the viscosity measurement method can obtain the same effect as item 4.

[0137] [Item 11] The method further includes a step of transmitting information to prompt the user to clean the suction unit. The control step includes a step of transmitting, in the transmitting step, cleaning warning information that warns the user to clean the suction unit when the second predetermined time has elapsed since the previous measurement in the measuring step. The viscosity measuring method according to claim 10.

[0138] As a result, the viscosity measurement method can obtain the same effect as item 5.

[0139] [Item 12] The transmission of the information includes at least one of audible output and screen display of the information to the worker. Item 12. The viscosity measuring method according to item 9 or 11.

[0140] As a result, the viscosity measurement method can obtain the same effect as item 6.

[0141] Although the embodiments have been described above with reference to the accompanying drawings, the present disclosure is not limited to such examples. It is clear that a person skilled in the art can conceive of various modifications, corrections, substitutions, additions, deletions, and equivalents within the scope of the claims, and it is understood that these also belong to the technical scope of the present disclosure. In addition, the components in the above-mentioned embodiments may be arbitrarily combined within the scope of the invention. [Industrial Applicability]

[0142] The present disclosure is useful for a printing apparatus, a viscosity measurement method, and the like that can obtain reliable measurement values ​​during the production of substrates. [Explanation of symbols]

[0143] 1 Printing device 11. Mask 11K Aperture Pattern 13 Print Head 15 Viscometer 15M motor 18 Thermometer 151 Screw 152 Cylindrical body 153 Torque Sensor 154 Introduction 155 Discharge section 32 Squeegee 64 Measuring part 65 Measurement control section 67 Temperature control unit 70 Viscosity measurement section KB board Pst solder paste TP Touch Panel

Claims

1. A printing device that prints solder paste on a substrate through a mask having a predetermined opening pattern, a suction section capable of introducing the solder paste on the mask through a suction port and discharging the solder paste through an opening; a measuring unit that measures the viscosity or a viscosity equivalent value of the solder paste introduced into the suction unit multiple times; a control unit that causes the measurement unit to measure the viscosity or the viscosity equivalent value of the solder paste when a first predetermined time has elapsed since a previous measurement by the measurement unit; A printing device having the above configuration.

2. the first predetermined time is a time during which the viscosity or the viscosity equivalent value of the solder paste introduced into the suction section does not exceed a predetermined range; The printing device of claim 1 .

3. A transmission unit that transmits information to prompt cleaning of the suction unit, The control unit causes the transmitting unit to transmit cleaning recommendation information that recommends cleaning of the suction unit when the first predetermined time has elapsed since the previous measurement by the measurement unit.

3. The printing device according to claim 1 or 2.

4. the control unit stops printing by the printing device when a second predetermined time longer than the first predetermined time has elapsed since the previous measurement by the measurement unit.

3. The printing device according to claim 1 or 2.

5. A transmission unit that transmits information to prompt cleaning of the suction unit, The control unit causes the transmitting unit to transmit cleaning warning information that warns the user to clean the suction unit when the second predetermined time has elapsed since the previous measurement by the measurement unit. The printing device according to claim 4.

6. The transmission of the information includes at least one of audible output and screen display of the information to the worker. The printing device according to claim 3 .

7. A viscosity measurement method for measuring the viscosity of a solder paste printed on a substrate through a mask having a predetermined opening pattern using a suction unit, comprising: the suction unit is capable of introducing the solder paste on the mask through a suction port and discharging it through an opening, an introduction step of introducing the solder paste on the mask into the inside of the suction portion; a measuring step of measuring the viscosity or a viscosity equivalent value of the solder paste introduced into the suction portion a plurality of times; a control step of measuring the viscosity or the viscosity equivalent value of the solder paste in the measuring step when a first predetermined time has elapsed since the previous measurement in the measuring step; The viscosity measuring method according to claim 1,

8. The predetermined time is a time during which the viscosity or the viscosity equivalent value of the solder paste introduced into the suction section does not exceed a predetermined range. The viscosity measuring method according to claim 7.

9. The method further includes a step of transmitting information to prompt the user to clean the suction unit. The control step includes a step of transmitting, in the transmitting step, cleaning recommendation information that recommends cleaning of the suction unit, when the first predetermined time has elapsed since the previous measurement in the measuring step. The viscosity measuring method according to claim 7 or 8.

10. the control step includes a step of stopping printing by the printing device having the suction unit when a second predetermined time longer than the first predetermined time has elapsed since the previous measurement in the measurement step. The viscosity measuring method according to claim 7 or 8.

11. The method further includes a step of transmitting information to prompt the user to clean the suction unit. The control step includes a step of transmitting, in the transmitting step, cleaning warning information for warning the user to clean the suction unit when the second predetermined time has elapsed since the previous measurement in the measuring step. The viscosity measuring method according to claim 10.

12. The transmission of the information includes at least one of audible output and screen display of the information to the worker. The viscosity measuring method according to claim 9.

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