Paste transfer device, screen printing device, and paste transfer method

Abstract

The purpose of the present invention is to provide a paste transfer device, a screen printing device, and a paste transfer method capable of suppressing the consumption of a sheet member and improving the productivity of a screen printing operation. A paste transfer operation is executed in which paste (Pst) on a current mask (13) (first mask) is placed and collected on a sheet member (25) covering a paste collection surface (24M) of a movable scraper (24), and thereafter the collected paste (Pst) is dropped onto a next mask (13) (second mask) different from the first mask and supplied. A determination (ST11, ST12) is made as to whether or not predetermined prescribed conditions are satisfied prior to execution of a paste transfer operation, the paste transfer operation is executed without updating the sheet member if the prescribed conditions are determined to be satisfied, and the paste transfer operation is executed (ST7) after updating the sheet member if the prescribed conditions are determined not to be satisfied (ST8 to ST10).

Description

Technical Field

[0001] The present invention relates to a paste transfer device, a screen printing device and a paste transfer method for transferring paste between two masks to be replaced. Background Art

[0002] In the past, a screen printing device makes a substrate contact with the lower surface of a mask having a pattern opening formed therein, and moves a scraper on the mask, thereby printing a paste such as solder on the substrate. Furthermore, when the type of substrate is changed, the used mask is removed from the screen printing device, and a new mask corresponding to the substrate after the type is changed is set in the screen printing device. In this case, the paste remaining in the used mask is recovered by a scraper provided in the screen printing device, and then supplied to (i.e. transferred to) a new mask and reused (for example, refer to Patent Document 1 below).

[0003] In the paste transfer device described in Patent Document 1, the upper surface of the scraper (grounding body) is covered with a sheet member, and the sheet member is wound onto a reel and renewed each time the paste is transferred. Therefore, even if part of the paste adheres to the sheet member during the transfer of the paste, the undesirable situation that part of the paste is mixed into the next transferred paste will not occur.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 6-262750 Summary of the invention

[0007] Problems to be solved by the invention

[0008] However, if the sheet member is replaced every time the paste is transferred, the sheet member is consumed quickly, and there is a problem that the productivity of the screen printing apparatus may be reduced due to the replacement work of the sheet member.

[0009] Therefore, an object of the present invention is to provide a paste transfer device, a screen printing device, and a paste transfer method that can suppress the consumption of a sheet member and improve the productivity of a screen printing operation.

[0010] Solutions to Solve Problems

[0011] The paste transferring device of the present invention performs a paste transferring action. In the paste transferring action, after the paste on the first mask is loaded and recovered on a sheet member covering the paste recovery surface of a freely movable scraper, the recovered paste is dropped and supplied to a second mask different from the first mask, wherein the paste transferring device comprises: a sheet member updating section, which updates the portion of the sheet member covering the paste recovery surface; and a control section, which controls the paste transferring action and the updating action of the sheet member performed by the sheet member updating section, wherein the control section judges whether a predetermined specified condition is met before performing the paste transferring action, and controls the paste transferring action and the updating action of the sheet member performed by the sheet member updating section based on the judgment result.

[0012] Another paste transfer device of the present invention performs a paste transfer action. In the paste transfer action, after the paste on the first mask is loaded and recovered on a sheet member covering the paste recovery surface of a freely movable scraper, the recovered paste is dropped and supplied to a second mask different from the first mask, wherein the paste transfer device comprises: a sheet member updating section, which updates the portion of the sheet member covering the paste recovery surface; a control section, which controls the paste transfer action and the update action of the sheet member performed by the sheet member updating section; and a mode selection section, which can select either a normal mode or a saving mode, wherein the control section, when the normal mode is selected by the mode selection section, performs the paste transfer action after causing the sheet member updating section to perform the update action of the sheet member, and when the saving mode is selected by the mode selection section, determines whether a predetermined condition is satisfied before performing the paste transfer action, and controls the paste transfer action and the update action of the sheet member performed by the sheet member updating section based on the determination result.

[0013] The screen printing device of the present invention performs a printing operation of applying paste to a substrate via a mask, wherein the screen printing device uses the paste transfer device of the present invention to transfer paste from the first mask to the second mask and continues the printing operation.

[0014] The paste transfer method of the present invention performs a paste transfer process, in which, after the paste on the first mask is placed and recovered on a sheet member covering a paste recovery surface of a freely movable scraper, the recovered paste is dropped and supplied to a second mask different from the first mask, wherein before performing the paste transfer process, it is judged whether a predetermined condition is satisfied, and if it is judged that the predetermined condition is satisfied, the sheet member is not updated but the paste transfer process is performed, and if it is judged that the predetermined condition is not satisfied, the paste transfer process is performed after the sheet member is updated.

[0015] Effects of the Invention

[0016] According to the present invention, it is possible to suppress the consumption of the sheet member and improve the productivity of the screen printing operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a side view of a screen printing apparatus including a paste transfer device according to an embodiment of the present invention.

[0018] Figure 2 This is a side view showing a scraper unit provided in a screen printing device (paste transfer device) according to an embodiment of the present invention together with a print head.

[0019] Figure 3 (a) and (b) are side views of a scraper unit included in the paste transfer device according to one embodiment of the present invention.

[0020] Figure 4 This is a block diagram showing a control system of the screen printing apparatus in one embodiment of the present invention.

[0021] Figure 5 (a), (b), and (c) are diagrams for explaining a paste transferring operation of a scraper unit included in the paste transferring device according to one embodiment of the present invention.

[0022] Figure 6 (a), (b), and (c) are diagrams for explaining a paste transferring operation of a scraper unit included in the paste transferring device according to one embodiment of the present invention.

[0023] Figure 7 (a), (b), and (c) are diagrams for explaining a paste transferring operation of a scraper unit included in the paste transferring device according to one embodiment of the present invention.

[0024] Figure 8 This is a flowchart showing the flow of a screen printing operation performed by the screen printing device (paste transfer device) in one embodiment of the present invention.

[0025] Description of Reference Numerals

[0026] 1 Screen printing device

[0027] 11. Substrate holding unit

[0028] 12 Substrate holding unit moving mechanism

[0029] 12a Horizontal moving part

[0030] 12b Lifting unit

[0031] 13 Mask (first mask) (second mask)

[0032] 14 Printing head

[0033] 14S Scraper

[0034] 14M Print head moving mechanism

[0035] 15 Lower connecting part

[0036] 16 Clamp

[0037] 17 Scraper unit

[0038] 21-unit base

[0039] 22 Lifting Cylinder

[0040] 23 Scraper retaining body

[0041] 24 Scraping piece

[0042] 24M Paste Recovery Surface

[0043] 25 sheet components

[0044] 26 Sheet component update unit

[0045] 26a Delivery reel

[0046] 26b Winding reel

[0047] 27 Tensioner

[0048] 31 Control Department

[0049] 32 Storage

[0050] 33 Counter (counting unit)

[0051] 34. Timer (timing unit)

[0052] KB Substrate

[0053] Pst ointment. DETAILED DESCRIPTION

[0054] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Figure 1 The screen printing device 1 of the present invention is shown. For the convenience of description, in this embodiment, the left and right directions (with respect to Figure 1 The direction perpendicular to the paper surface of the image is set as the X direction, and the front-back direction (the left-right direction of the paper surface) is set as the Y direction. In addition, the up-down direction is set as the Z direction.

[0055] The screen printing device 1 is a device for printing a paste Pst such as solder on an electrode pattern (not shown) provided on a substrate KB, and includes a substrate holding portion 11 for holding the substrate KB and a substrate holding portion moving mechanism 12 for moving the substrate holding portion 11 in the XYZ directions. A mask 13 is provided above the substrate holding portion 11, and a printing head 14 is provided above the mask 13 so as to be movably provided.

[0056] exist Figure 1 In the embodiment, the substrate holding part 11 includes a lower receiving part 15 and a pair of clampers 16. The substrate holding part 11 supports (receives) the lower surface of the substrate KB by the lower receiving part 15, and clamps and holds both ends of the substrate KB received by the lower receiving part 15 by the clampers.

[0057] The substrate holding part moving mechanism 12 includes a horizontal moving part 12a that moves the substrate holding part 11 in a horizontal plane (XY plane) and a lifting part 12b that lifts and lowers the substrate holding part 11. The substrate holding part moving mechanism 12 moves the substrate holding part 11 holding the substrate KB in a horizontal plane (XY plane) using the horizontal moving part 12a, and lifts and lowers the substrate holding part 11 using the lifting part 12b.

[0058] The mask 13 is made of a metal plate and has a rectangular shape extending along a horizontal plane (XY plane). The peripheral portion of the mask 13 is held by a rectangular mask frame 13W. A pattern opening (not shown) formed in a configuration corresponding to the configuration of the electrode pattern of the substrate KB is provided in the central portion of the mask 13.

[0059] exist Figure 1 as well as Figure 2 In the embodiment, the print head 14 extends in the X direction and moves in the Y direction under the action of a print head moving mechanism 14M composed of a ball screw mechanism or the like. The print head 14 has two scrapers 14S arranged opposite to each other in the Y direction. Each scraper 14S has a shape of a "scraper" extending in the X direction. The two scrapers 14S can be raised and lowered independently relative to the print head 14.

[0060] exist Figure 1 as well as Figure 2In the embodiment, a scraper unit 17 is connected to the print head 14. The scraper unit 17 repeatedly performs a paste transfer operation of collecting the paste Pst on the mask 13 and transferring (ie, transferring) it to the mask 13 to be set next, as will be described later.

[0061] First, the structure of the scraper unit 17 will be described. Figure 2 In the embodiment, the scraper unit 17 includes: a unit base 21 extending horizontally from the print head 14; a lifting cylinder 22 provided on the unit base 21; a scraper holder 23 which is lifted and lowered by the lifting cylinder 22; and a scraper 24 held by the scraper holder 23. The scraper 24 holds the base end 24K on the scraper holder 23 and extends in a cantilevered state with the front end 24T facing the scraper 14S side. The scraper 24 has an inclined shape ( Figure 3 (a), (b)).

[0062] The unit base 21 is connected to the print head 14, so when the print head 14 moves in the Y direction, the scraper unit 17 moves in the Y direction together with the print head 14. When the lifting cylinder 22 is operated to lift the scraper holder 23, the scraper 24 held by the scraper holder is lifted relative to the unit base 21.

[0063] exist Figure 2 as well as Figure 3 In (a) and (b), the upper surface of scraper 24 (specifically, a certain area of ​​the upper surface of scraper 24 including tip 24T) serves as paste collecting surface 24M. Paste collecting surface 24M is covered with sheet member 25 .

[0064] The sheet member 25 is made of, for example, a strip-shaped member made of vinyl. In the present embodiment, the sheet member 25 extends from the upper surface of the scraper 24 (i.e., the paste recovery surface 24M) to the lower surface of the scraper 24, and one end (the end extending along the upper surface of the scraper 24) is held by the delivery reel 26a, and the other end (the end extending along the lower surface of the scraper 24) is held by the winding reel 26b ( Figure 2 as well as Figure 3 (a), (b)).

[0065] exist Figure 2 as well as Figure 3In (a) and (b), the delivery reel 26a and the winding reel 26b are respectively mounted on the scraper holder 23, and a tensioning wheel 27 is mounted below the delivery reel 26a and the winding reel 26b of the scraper holder 23. The tensioning wheel 27 applies force to the portion between the delivery reel 26a of the sheet member 25 and the front end 24T of the scraper 24 toward the base end 24K side of the scraper 24, thereby the sheet member 25 is in a state of extending along the paste recovery surface 24M.

[0066] When the delivery reel 26a and the take-up reel 26b are moved in the same direction, the portion of the sheet member 25 covering the paste recovery surface 24M of the scraper 24 moves in the up-down direction along the paste recovery surface 24M. Figure 3 The counterclockwise direction in (a) and (b) Figure 3 The arrow R1 shown in (b) of FIG. 1 is rotated, and the winding reel 26b is moved to Figure 3 The clockwise direction in (a) and (b) Figure 3 When the delivery reel 26a delivers the sheet member 25 and the winding reel 26b winds up the sheet member 25, the sheet member 25 descends along the paste recovery surface 24M ( Figure 3 (b) as indicated by arrow S).

[0067] Hereinafter, the rotation direction of the delivery reel 26a and the winding reel 26b in the direction in which the sheet member 25 descends along the paste collection surface 24M is referred to as the "forward direction". In contrast, the rotation direction of the delivery reel 26a and the winding reel 26b in the direction in which the sheet member 25 ascends along the paste collection surface 24M is referred to as the "reverse direction".

[0068] When the delivery reel 26a and the winding reel 26b are rotated in the forward direction as described above and the sheet member 25 is lowered along the paste recovery surface 24M, the area RY1 of the sheet member 25 covering the paste recovery surface 24M is transported to the lower surface side of the scraper 24, and the new area RY2 of the sheet member 25 is transported to the paste recovery surface 24M from the base end 24K side of the scraper 24 ( Figure 3 (a) → Figure 3 (b)). As a result, the portion of the sheet member 25 covering the paste recovery surface 24M is replaced from the area RY1 of the sheet member 25 to the area RY2, and the sheet member 25 covering the paste recovery surface 24M is in an updated state. Hereinafter, the updating of the sheet member 25 covering the paste recovery surface 24M of the scraper 24 is referred to as "updating of the sheet member 25".

[0069] As described above, in the present embodiment, the feed reel 26 a and the wind-up reel 26 b constitute the sheet member renewal unit 26 that renews the portion of the sheet member 25 that covers the paste collection surface 24M.

[0070] Figure 4 FIG. 2 shows a control system of the screen printing device 1. Figure 4 In the screen printing apparatus 1, the control unit 31 controls the lower receiving action of the substrate KB by the lower receiving unit 15 of the substrate holding unit 11, the clamping action of the substrate KB by the clamper 16, and the movement action of the substrate holding unit 11 along the XYZ direction by the horizontal moving unit 12a and the lifting unit 12b of the substrate holding unit moving mechanism 12. In addition, the control unit 31 controls the lifting action of the scraper 14S of the print head 14 and the movement action of the print head 14 by the print head moving mechanism 14M. In addition, the control unit 31 controls the rotation of the delivery reel 26a and the winding reel 26b of the scraper unit 17.

[0071] When the screen printing apparatus 1 performs screen printing, first, paste Pst is supplied to the upper surface of the mask 13. The supply of the paste Pst is different from the paste supply operation performed by the scraper unit 17 described later, and new paste Pst is supplied onto the mask 13.

[0072] As a case where a new paste Pst is supplied to the mask 13, for example, it can be mentioned that it is at the beginning of the first screen printing operation of the day, or at the beginning of the first screen printing operation when the type of the substrate KB is changed. In addition, it can be mentioned that the paste Pst supplied to the mask 13 is removed because the quality is reduced due to being left for a certain period of time, or just after the mask 13 is replaced. The supply of this new paste Pst to the mask 13 is performed manually by the operator, or by using a paste supply device (not shown) provided in the screen printing device 1.

[0073] After the new paste Pst is supplied onto the mask 13 as described above, the screen printing device 1 performs a printing operation. The printing operation is performed by lowering one of the two scrapers 14S provided in the print head 14 so that the lower end thereof abuts against the upper surface of the mask 13 and in this state, the print head 14 is moved in the Y direction by the print head moving mechanism 14M ( Figure 1 By this printing operation, the paste Pst on the mask 13 is scraped by the squeegee 14S, and the paste Pst passes through the pattern opening of the mask 13 and is applied to the electrode pattern.

[0074] When the screen printing device 1 needs to change the type of substrate KB after performing the above-mentioned printing operation on multiple substrates KB, the mask 13 is replaced according to the type of substrate KB. The screen printing device 1 causes the scraper unit 17 to perform the following paste transfer operation during the mask 13 replacement operation: after the scraper 24 (directly the scraper unit 17) is moved to place and recover the paste Pst on the current mask 13 (first mask) on the sheet member 25 covering the paste recovery surface 24M of the scraper 24, the recovered paste Pst is dropped and supplied to the next mask 13 (another mask 13 different from the first mask, i.e., the second mask) after replacement.

[0075] In the paste transfer operation, first, the paste Pst on the current mask 13 (first mask) is recovered. In the paste Pst recovery operation, first, the lifting cylinder 22 is operated to lower the scraper holder 23 ( Figure 5 The lower surface of the scraper 24 (specifically, the sheet member 25 located on the lower surface side of the scraper 24) is brought into contact with the mask 13 as indicated by the arrow B1 shown in (a). At this time, the front end 24T of the scraper 24 is located near the paste Pst to be recovered ( Figure 5 (a)).

[0076] After the lower surface of the scraper 24 abuts against the mask 13, the take-up reel 26b is rotated in the reverse direction while the delivery reel 26a is stopped ( Figure 6 The sheet member 25 on the lower side of the scraper 24 is released by a predetermined length to relax the sheet member 25 ( Figure 6 Here, the length of the delivered sheet member 25 is the amount by which the sheet member 25 moves upward (toward the base end portion 24K side) on the paste recovery surface 24M side by the subsequent reverse rotation of the delivery reel 26a. After the sheet member 25 of the predetermined length is released from the winding reel 26b, the rotation of the winding reel 26b is stopped.

[0077] After the sheet member 25 on the lower side of the scraper 24 is fed out by a predetermined length by rotating the winding reel 26b in the reverse direction, the screen printing device 1 operates the print head moving mechanism 14M to move the print head 14 (i.e., the scraper unit 17) in a direction (set as a forward direction) in which the front end 24T of the scraper 24 approaches the paste Pst on the mask 13. Figure 6 Thus, the front end 24T of the scraper 24 approaches the paste Pst on the mask 13 while sliding on the mask 13.

[0078] After the front end 24T of the scraper 24 approaches the paste Pst on the mask 13 and enters the paste Pst ( Figure 6 (b)), the take-up reel 26a is rotated in the reverse direction instead of rotating the take-up reel 26b ( Figure 6 As a result, the paste Pst on the mask 13 moves together with the sheet member 25 moving upward along the upper surface of the scraper 24, and climbs onto the paste recovery surface 24M of the scraper 24 (specifically, onto the sheet member 25 covering the paste recovery surface 24M). Figure 6 (b) and (c) as shown in arrow D).

[0079] At this time, the sheet member 25 pulled up by the delivery reel 26a along the paste collecting surface 24M of the scraper 24 corresponds to the sheet member 25 slackened on the lower surface side of the scraper 24. Therefore, when the sheet member 25 is pulled up by the delivery reel 26a, the load torque received by the delivery reel 26a is extremely small.

[0080] As described above, by rotating the delivery reel 26a in the reverse direction, the paste Pst on the mask 13 moves toward the paste recovery surface 24M of the scraper 24, and the slack of the sheet member 25 on the lower surface side of the scraper 24 disappears. After the paste Pst on the mask 13 climbs onto the paste recovery surface 24M of the scraper 24 ( Figure 5 (b)) to stop the rotation of the delivery reel 26a. Then, the lifting cylinder 22 is operated to raise the unit base 21 ( Figure 5 As a result, the paste recovery operation performed by the scraper unit 17 is completed.

[0081] After the recovery operation of the paste Pst is completed, a new next mask 13 (second mask) is set and the replacement operation of the mask 13 is completed, the screen printing apparatus 1 causes the scraper unit 17 to perform the paste supply operation. In the paste supply operation, initially, the print head 14 (i.e., the scraper unit 17) is moved by the print head moving mechanism 14M so that the scraper unit 17 is located above the replaced new mask 13. At this time, the scraper unit 17 is arranged so that the paste Pst recovered by the paste recovery operation is located above the supply location of the paste Pst in the replaced new mask 13.

[0082] After the scraper unit 17 is located above the new mask 13, the lifting cylinder 22 is operated to lower the unit base 21 ( Figure 7 The front end 24T of the scraper 24 is brought into contact with the new mask 13 (arrow B1 shown in (a)). Figure 7After the front end 24T of the scraper 24 contacts the new mask 13, the control unit 31 activates the print head moving mechanism 14M to move the print head 14 (i.e., the scraper unit 17) in a direction away from the paste Pst by the front end 24T of the scraper 24 (set as a backward direction). Figure 7 Then, the delivery reel 26a and the winding reel 26b are synchronously rotated in the forward direction (as indicated by the arrow C2 in (b)). Figure 7 The sheet member 25 covering the paste recovery surface 24M is moved (descended) toward the front end 24T of the scraper 24 (arrows R1, R2 shown in (b)) ( Figure 7 (b) as indicated by arrow S).

[0083] When the sheet member 25 covering the paste collecting surface 24M is lowered while the print head 14 is moved in the backward direction, the paste Pst climbing onto the paste collecting surface 24M of the scraper 24 falls onto the mask 13 (second mask) ( Figure 7 (c)). After the paste Pst falls on the mask 13 (second mask), the rotation of the delivery reel 26a and the winding reel 26b is stopped. Thus, the paste supply operation is completed (and thus the paste transfer operation is completed).

[0084] In the above-mentioned paste supplying operation, the length of the sheet member 25 released by the delivery reel 26a and wound up by the winding reel 26b is set to the length of the sheet member 25 released by the winding reel 26b at the beginning of the paste collecting operation (the length of the region RY1) in this embodiment. As a result, the position of the region RY1 on the upper surface of the scraper 24 after the end of the paste supplying operation is substantially the same as the position of the region RY1 on the upper surface of the scraper 24 before the start of the paste collecting operation. Therefore, before and after the paste transferring operation, the position of the sheet member 25 relative to the upper surface of the scraper 24 does not change ( Figure 6 (a) → Figure 6 (b) → Figure 6 (c) → Figure 7 (a) → Figure 7 (b) → Figure 7 In (c)), the sheet member 25 is not renewed due to the paste transfer operation.

[0085] After the paste transfer operation is completed, the screen printing device 1 repeatedly performs the screen printing operation using the new mask 13 (second mask) after replacement, to which the paste Pst is transferred from the mask 13 (first mask) before replacement. And, when it is necessary to replace the mask 13 next, the screen printing device 1 updates the sheet member 25 according to the above-mentioned method ( Figure 3 (a) → Figure 3(b)) or when a predetermined condition is satisfied, the sheet member 25 is not updated but the scraper unit 17 is caused to perform the paste transfer operation.

[0086] Here, the reason for replacing the sheet member 25 before the paste transfer operation is performed as described above is to prevent the paste Pst attached to the sheet member 25 by the previous paste transfer operation from being mixed into the paste Pst to be transferred later (mixing of new and old pastes Pst) and preventing the quality of the paste Pst from being reduced. In order to prevent such mixing of new and old pastes Pst, it is sufficient to always replace the sheet member 25 after the scraper unit 17 completes the paste transfer operation.

[0087] However, even if the sheet member 25 is not necessarily updated after the paste transfer operation is completed as described above, it is sometimes possible to allow the mixing of new and old pastes Pst depending on the conditions (that is, it is considered that the quality of the paste Pst will not be reduced even if the new and old pastes Pst are mixed). In this embodiment, not only is there a mode in which the sheet member 25 is always updated before the paste transfer operation is performed (referred to as the "normal mode"), but there is also a mode in which the sheet member 25 is updated before the paste transfer operation is performed as a principle and the updating of the sheet member 25 is omitted when the specified conditions are met, thereby saving the sheet member 25 (referred to as the "saving mode"), and one of the two modes can be arbitrarily selected. The following is an explanation.

[0088] exist Figure 4 In the embodiment, the control unit 31 includes a storage unit 32, a counter 33, a timer 34, and a determination unit 35. The control unit 31 is connected to a mode selection unit 36.

[0089] The storage unit 32 stores information on the paste Pst in addition to the execution program of the screen printing operation executed by the screen printing apparatus 1. The information on the paste Pst refers to information such as the type of paste Pst that changes as the screen printing operation progresses and is recorded in the execution program of the screen printing operation.

[0090] The counter 33 functions as a counting unit that counts the number of times (referred to as the "continuous collection number") that the paste Pst is continuously collected by the paste collection surface 24M without using the feeding reel 26a and the winding reel 26b (i.e., the sheet member updating unit 26) to update the sheet member 25. The timer 34 functions as a timing unit that counts the elapsed time (referred to as the "standing time") from when the paste Pst to be collected, i.e., the paste Pst supplied to the current mask 13 (first mask), is left (becomes unused).

[0091] When it is determined that the mask 13 needs to be replaced, the judgment unit 35 judges whether the type of paste Pst used before and after the replacement of the mask 13 is the same. Furthermore, when it is determined that the type of paste Pst used before and after the replacement of the mask 13 is the same (wherein the saving mode described later is selected), it is then judged whether predetermined conditions (two conditions) are satisfied. In the present embodiment, one of the two conditions (the first condition) is "the number of consecutive recycling times counted by the counter 33 is less than the predetermined number of times", and the other of the two conditions (the second condition) is "the placement time counted by the timer 34 is shorter than the predetermined time".

[0092] When judging whether the types of the paste Pst used before and after the replacement of the mask 13 are the same, the judging unit 35 compares the type of the paste Pst used in the mask 13 before the replacement with the type of the paste Pst to be used in the mask 13 after the replacement based on the information stored in the storage unit 32. And, when it is detected that the type of the paste Pst used in the mask 13 before the replacement is the same as the type of the paste Pst to be used in the mask 13 after the replacement, it is judged that the types of the paste Pst used before and after the replacement of the mask 13 are the same.

[0093] When determining whether the first condition is satisfied, the determination unit 35 compares the number of consecutive collections counted by the counter 33 with a predetermined number of times (eg, 3 times). If the number of consecutive collections is less than the predetermined number of times, the determination unit 35 determines that the first condition is satisfied.

[0094] Furthermore, the determination unit 35 compares the idle time measured by the timer 34 with a predetermined time (e.g., 20 minutes) when determining whether the second condition is satisfied. If the idle time is shorter than the predetermined time, the determination unit 35 determines that the second condition is satisfied.

[0095] The determination unit 35 determines that all the prescribed conditions are satisfied when it is determined that both of the above conditions are satisfied, that is, when it is detected that the counted number of consecutive collections is less than the predetermined number of times and when it is detected that the timed storage time is shorter than the predetermined time. On the other hand, as long as it is determined that one of the two conditions is not satisfied, it is determined that the prescribed condition is not satisfied.

[0096] The mode selection unit 36 ​​is composed of, for example, buttons displayed on a touch panel (not shown) provided in the screen printing device 1. The mode selection unit 36 ​​can select either a "normal mode" or a "saving mode". When the "normal mode" is selected from the mode selection unit 36, the control unit 31 enters the normal mode, and when the "saving mode" is selected from the mode selection unit 36, the control unit 31 enters the saving mode.

[0097] When the control unit 31 selects the normal mode using the mode selection unit 36, the control unit 31 causes the sheet member updating unit 26 to always perform the updating operation of the sheet member 25 before performing the paste transfer operation. When the control unit 31 selects the saving mode using the mode selection unit 36, the control unit 31 causes the sheet member updating unit 26 to perform the updating operation of the sheet member 25 before performing the paste transfer operation as a rule, but does not cause the sheet member updating unit 26 to perform the updating operation of the sheet member 25 when it is determined that a predetermined condition is satisfied.

[0098] Figure 8 The flowchart of FIG. 1 shows the process of the screen printing operation performed by the screen printing device 1 in the present embodiment. As shown in the flowchart, the screen printing device 1 performs a printing operation (step ST1). When the mask 13 needs to be replaced (step ST2), the control unit 31 (judgment unit 35) determines whether the types of the paste Pst used before and after the replacement of the mask 13 are the same based on the information stored in the storage unit 32 (step ST3). And, when it is determined that the types of the paste Pst are different, the mask 13 is replaced together with the paste Pst (step ST4), and the paste Pst is waited to be newly supplied to the newly set mask 13 (step ST5), and the process returns to step ST1. And, the printing operation is performed using the (newly set) mask 13 replaced in step ST4 and the paste Pst newly supplied in step ST5.

[0099] On the other hand, when the control unit 31 determines in step ST3 that the type of paste Pst used before and after the replacement of the mask 13 is the same, it determines whether the mode currently selected by the mode selection unit 36 ​​is the normal mode or the saving mode (step ST6). Furthermore, when the control unit 31 determines in step ST6 that the currently selected mode is the normal mode, it causes the sheet member updating unit 26 to update the sheet member 25 (step ST7), and causes the scraper unit 17 to perform the paste recovery operation (step ST8).

[0100] After step ST8, the mask 13 is replaced with a new mask 13 (step ST9), and the control unit 31 causes the scraper unit 17 to perform a paste supply operation (step ST10). After causing the scraper unit 17 to perform a paste transfer operation, the process returns to step ST1, and a printing operation is performed using the mask 13 replaced (newly installed) in step ST9 and the paste Pst supplied in step ST10 (paste Pst transferred from the previous mask 13).

[0101] On the other hand, when the control unit 31 determines in step ST6 that the currently selected mode is the saving mode, based on the number of continuous recovery times counted by the counter (the number of times the paste Pst is continuously recovered using the paste recovery surface 24M without performing the updating operation of the sheet member 25 by the sheet member updating unit 26), the control unit 31 investigates whether the number of continuous recovery times is less than a predetermined number of times (step ST11).

[0102] When the control unit 31 detects in step ST11 that the number of consecutive collection times is less than the prescribed number, the control unit 31 then checks whether the standing time measured by the timer 34 (the time elapsed since the paste Pst to be collected was placed) is shorter than the predetermined prescribed time (step ST12). As a result, when it is detected that the standing time measured by the timer 34 is shorter than the prescribed time, the scraper unit 17 is made to collect the paste instead of the sheet member renewal unit 26 (step ST8). After the mask 13 is replaced with a new mask 13 (step ST9), the scraper unit 17 is made to supply the paste (step ST10), and the process returns to step ST1 to perform the printing operation.

[0103] On the other hand, when the control unit 31 detects that the number of continuous collection times is greater than the prescribed number of times in step ST11 and that the standing time is longer than the prescribed time in step ST12, the control unit 31 causes the sheet member renewal unit 26 to perform a renewal operation of the sheet member 25 (step ST7). Furthermore, after causing the scraper unit 17 to perform a paste collection operation (step ST8) and replacing the mask 13 with a new mask 13 (step ST9), the scraper unit 17 is caused to perform a paste supply operation (step ST10), and the process returns to step ST1.

[0104] In this way, in the screen printing operation performed by the screen printing device 1, the process of performing the printing action of screen printing on the substrate KB is repeatedly performed (step ST1), and when the mask 13 is replaced, after the paste Pst on the current mask 13 (first mask) is placed and recovered on the paste recovery surface 24M of the scraper 24, the paste transfer process (steps ST8 to ST10) is performed to drop and supply the recovered paste Pst to the next mask 13 (second mask).

[0105] Furthermore, when the normal mode is selected, the paste transfer process is always performed after the sheet member 25 is updated, but when the saving mode is selected, the paste transfer process is performed after the sheet member 25 is updated unless a predetermined condition is satisfied. That is, when the saving mode is selected, the sheet member 25 is not updated but the paste transfer process is performed on the condition that a predetermined condition is satisfied, so that the consumption of the sheet member 25 is suppressed.

[0106] The paste transfer device in the present embodiment is a device that performs a paste transfer action. In the paste transfer action, after the paste Pst on the current mask 13 (first mask) is loaded and recovered on the sheet member 25 covering the upper surface (paste recovery surface 24M) of the freely movable scraper 24, the recovered paste Pst is dropped and supplied to the next mask 13 (second mask) different from the first mask. The paste transfer device as a device included in the above-mentioned screen printing device 1 comprises: a sheet member updating unit 26, which updates the portion of the sheet member 25 covering the paste recovery surface 24M; and a control unit 31, which controls the paste transfer action and the updating action of the sheet member 25 performed by the sheet member updating unit 26. The control unit 31 judges whether a predetermined condition is met before performing the paste transfer action, and controls the paste transfer action performed by the scraper 24 and the updating action of the sheet member 25 performed by the sheet member updating unit 26 based on its judgment result. In detail, when the control unit 31 determines that the above-mentioned specified conditions are met, the control unit 31 does not cause the sheet component updating unit 26 to update the sheet component 25 but instead performs the paste transfer action. When it is determined that the specified conditions are not met (as long as part of the multiple conditions are not met), the control unit 31 causes the sheet component updating unit 26 to update the sheet component 25 and then performs the paste transfer action.

[0107] In addition, the paste transfer method performed by the paste transfer device is a method for performing a paste transfer process (steps ST8 to ST10) in which, after the paste Pst on the current mask 13 (first mask) is placed and recovered on the sheet member 25 covering the upper surface (paste recovery surface 24M) of the freely movable scraper 24, the recovered paste Pst is dropped and supplied to the next mask 13 (second mask) different from the first mask. In the paste transfer method, before performing the paste transfer process, it is determined whether a predetermined condition is satisfied (steps ST11 and ST12), and when it is determined that the predetermined condition is satisfied, the paste transfer process is performed without updating the sheet member 25, and when it is determined that the predetermined condition is not satisfied, the paste transfer operation is performed after the sheet member 25 is updated (step ST7).

[0108] In the paste transfer device (paste transfer method) of the present embodiment, the sheet member 25 is not necessarily updated before the paste transfer operation is performed. When it is determined that a predetermined condition is satisfied, the paste transfer operation is performed without updating the sheet member. Therefore, compared with the case where the sheet member 25 is always updated before the paste transfer operation is performed, it is possible to suppress the consumption of the sheet member 25. In addition, the frequency of the replacement operation of the sheet member can be reduced, so that the productivity of the operation (screen printing operation) performed by the screen printing device 1 can be improved.

[0109] In addition, the screen printing device 1 in this embodiment performs a printing operation of applying paste Pst to the substrate KB via the mask 13, but can utilize the paste transferring device (paste transferring method) in this embodiment to transfer the paste Pst from one mask 13 (first mask) to the next mask 13 (second mask) and continue the operation, so that the paste Pst is not wasted, and the sheet member 25 can be saved and cost-optimized operation can be performed.

[0110] As described above, in the screen printing device 1 (paste transfer device, paste transfer method) in the present embodiment, when predetermined conditions are met, the sheet member is not updated but the paste transfer action is performed, thereby suppressing the consumption of the sheet member 25, thereby reducing the frequency of the sheet member replacement operation and improving the productivity of the operation (screen printing operation) performed by the screen printing device 1.

[0111] So far, the embodiment of the present invention has been described, but the present invention is not limited to the above content, and various modifications are possible. For example, the sheet member renewal unit 26 shown in the above embodiment is a structure composed of the delivery reel 26a and the winding reel 26b, but the sheet member renewal unit 26 can be any other structure as long as it can renew the portion of the sheet member 25 covering the paste recovery surface 24M. In addition, in the above embodiment, it is a structure that can select either the normal mode or the saving mode, but it may be that such a mode selection cannot be performed and only the operation equivalent to the saving mode is always performed.

[0112] In addition, the action mode of the sheet member 25 relative to the paste recovery surface 24M in the above-mentioned paste transferring action (paste recovery action and paste supply action) is only an example, and as long as the paste Pst on the mask 13 can be made to climb onto the paste recovery surface 24M of the scraper 24 in the paste recovery action, and the paste Pst that has climbed onto the paste recovery surface 24M can be dropped onto the mask 13 in the paste supply action, the action mode of the sheet member 25 is not limited.

[0113] Industrial Applicability

[0114] Provided are a paste transfer device, a screen printing device, and a paste transfer method that can suppress the consumption of a sheet member and improve the productivity of a screen printing operation.

Claims

1. A paste transfer device that performs a paste transfer operation, in which, after the paste on a first mask is placed and recovered on a sheet member covering a paste recovery surface of a freely movable scraper, the recovered paste is dropped and supplied onto a second mask different from the first mask, wherein: The paste transfer device comprises: a sheet member renewal section that renews a portion of the sheet member that covers the paste collecting surface; and a control unit that controls the paste transfer operation and the sheet member renewal operation performed by the sheet member renewal unit, The control unit determines whether a predetermined condition is satisfied before executing the paste transfer operation, and controls the paste transfer operation and the updating operation of the sheet member by the sheet member updating unit based on the determination result.

2. The paste transfer device according to claim 1, wherein: The control unit performs the paste transfer operation without causing the sheet member updating unit to perform the sheet member updating operation when it is determined that the predetermined condition is satisfied, and performs the paste transfer operation after causing the sheet member updating unit to perform the sheet member updating operation when it is determined that the predetermined condition is not satisfied.

3. The paste transfer device according to claim 1, wherein: The paste transfer device further includes a counting unit for counting the number of continuous collection times, which is the number of times the paste is continuously collected using the paste collection surface without performing the sheet member renewal operation by the sheet member renewal unit. The control unit determines that a part of the predetermined condition is satisfied when detecting that the number of consecutive collection times counted by the counting unit is smaller than a predetermined number of times.

4. The paste transfer device according to claim 1, wherein: The paste transfer device further includes a timing unit for timing a placement time, wherein the placement time is an elapsed time from when the paste to be collected is placed. The control unit determines that a part of the predetermined condition is satisfied when detecting that the idle time measured by the timing unit is shorter than a predetermined time.

5. A paste transfer device that performs a paste transfer operation, in which, after the paste on a first mask is placed and recovered on a sheet member covering a paste recovery surface of a freely movable scraper, the recovered paste is dropped and supplied onto a second mask different from the first mask, wherein: The paste transfer device comprises: a sheet member renewal section that renews a portion of the sheet member that covers the paste recovery surface; a control unit that controls the paste transfer operation and the sheet member renewal operation performed by the sheet member renewal unit; and a mode selection unit capable of selecting either a normal mode or a saving mode, When the normal mode is selected by the mode selection unit, the control unit performs the paste transferring action after causing the sheet component updating unit to perform the sheet component updating action. When the saving mode is selected by the mode selection unit, the control unit determines whether a predetermined condition is satisfied before performing the paste transferring action, and controls the paste transferring action and the sheet component updating action performed by the sheet component updating unit based on the determination result.

6. The paste transfer device according to claim 5, wherein: The control unit performs the paste transfer operation without causing the sheet member updating unit to perform the sheet member updating operation when it is determined that the predetermined condition is satisfied, and performs the paste transfer operation after causing the sheet member updating unit to perform the sheet member updating operation when it is determined that the predetermined condition is not satisfied.

7. A screen printing device for performing a printing operation of applying a paste to a substrate via a mask, wherein: The screen printing apparatus transfers paste from the first mask to the second mask using the paste transfer device according to any one of claims 1 to 6, and continues the printing operation.

8. A paste transfer method, performing a paste transfer step, in which, after the paste on a first mask is placed and recovered on a sheet member covering a paste recovery surface of a freely movable scraper, the recovered paste is dropped and supplied onto a second mask different from the first mask, wherein: Before executing the paste transfer process, it is determined whether a predetermined condition is satisfied. If it is determined that the predetermined condition is satisfied, the paste transfer process is executed without updating the sheet member. If it is determined that the predetermined condition is not satisfied, the paste transfer process is executed after updating the sheet member.

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