JP7665542B2 - Screen printer and solder paste rolling method - Google Patents

Description

The technology disclosed in this specification relates to a screen printer and a solder paste rolling method.

Conventionally, screen printers that use a mask to print a circuit pattern on a substrate print the circuit pattern by moving a squeegee while the substrate is in close contact with the underside of the mask, thereby rolling the solder paste on the mask.
In such a screen printer, if there is a slack time during printing of the board, the viscosity of the solder paste on the mask increases during that time, which can result in poor printing when printing is resumed. For this reason, in the past, when there was a slack time during printing, the solder paste was rolled to prevent the viscosity of the solder paste from increasing (see, for example, Patent Document 1).

Specifically, the cream solder printing method described in Patent Document 1 performs the stirring operation (corresponding to rolling) using a pseudo-substrate for the stirring operation, which is not an actual production board, and an upstream pseudo-substrate stocker for stocking pseudo-substrates is arranged upstream of the main body of the cream solder printing device (corresponding to a screen printing machine). When the upstream pseudo-substrate stocker receives a command to load the pseudo-substrate, it loads it. The cream solder printing device presses the loaded pseudo-substrate against the back surface of the screen (corresponding to a mask) and performs a pseudo-filling operation under exactly the same conditions as during actual production, thereby stirring the cream solder (corresponding to solder paste) (the second embodiment of the same document).

JP 2004-25644 A

However, the solder paste printing method described in Patent Document 1 has room for improvement in terms of simplifying the configuration for stirring the solder paste.
This specification discloses a technique that allows rolling of solder paste with a simple configuration.

A screen printing machine that uses a mask to print a circuit pattern on a substrate, the machine comprising: a conveyor that transports the substrate to a printing position; a printing table that brings the substrate transported to the printing position by the conveyor into close contact with the underside of the mask; a printing unit that has a squeegee and prints the circuit pattern on the substrate by moving the squeegee while the substrate is in close contact with the underside of the mask to roll the solder paste on the mask; and a rolling substrate supply unit that supports a rolling substrate used for rolling the solder paste when a predetermined condition is met and supplies the rolling substrate to the conveyor. , and the rolling substrate supply unit is a first substrate support unit that supports the rolling substrate above the conveyor at a position that does not overlap with the mask in a top view, and has a pair of pedestal parts that are horizontally spaced apart from each other and a pair of moving parts that move the pedestal parts in the horizontal direction, and supports both ends of the rolling substrate with the pair of pedestal parts, and a substrate lifting unit that lifts and lowers the rolling substrate supported by the first substrate support unit, and has a second substrate support part that supports the rolling substrate from below and a lifting part that lifts and lowers the second substrate support part.

The above configuration allows solder paste rolling to be performed with a simple configuration.

FIG. 1 is a perspective view of a screen printing machine according to a first embodiment; Schematic diagram of a screen printing machine seen from the front FIG. 3 is a perspective view of a mask member; Schematic diagram of a screen printing machine seen from above Schematic diagram of a screen printing machine seen from the left side Schematic diagram of the entrance conveyor seen from the right side Block diagram showing the electrical configuration of a screen printing machine Flowchart of solder paste rolling process FIG. 13 is a schematic diagram showing a state in which a rolling substrate is supported by a first substrate support portion; FIG. 1 is a schematic diagram showing a rolling substrate being lifted by a substrate lifting unit; FIG. 13 is a schematic diagram showing a state in which a pair of pedestals are spaced apart from each other; A schematic diagram showing a state in which a rolling substrate is supplied to an entrance side conveyor.

(Outline of this embodiment)
(1) A screen printer according to the present disclosure is a screen printer that prints a circuit pattern on a substrate using a mask, the screen printer including: a conveyor that transports the substrate to a printing position; a printing table that brings the substrate transported to the printing position by the conveyor into close contact with an underside of the mask; a printing unit that has a squeegee and moves the squeegee while the substrate is in close contact with the underside of the mask to roll the solder paste on the mask, thereby printing the circuit pattern on the substrate; and a printing unit that supports a rolling substrate used for rolling the solder paste when a predetermined condition is met, and supplies the rolling substrate to the conveyor. and a rolling substrate supply unit for supplying the rolling substrate to the mask from above the conveyor, the rolling substrate supply unit comprising a first substrate support unit for supporting the rolling substrate above the conveyor at a position not overlapping with the mask in a top view, the first substrate support unit having a pair of pedestal portions spaced horizontally from each other and a pair of moving units for moving the pedestal portions horizontally, the first substrate support unit supporting both ends of the rolling substrate with the pair of pedestal portions, and a substrate lifting unit for raising and lowering the rolling substrate supported by the first substrate support unit, the substrate lifting unit having a second substrate support portion for supporting the rolling substrate from below and a lifting unit for raising and lowering the second substrate support portion.

In the solder paste printing method described in the above-mentioned Patent Document 1, the upstream side pseudo-substrate stocker that stocks the pseudo-substrates is configured as a separate device from the solder paste printing device. Because the upstream side pseudo-substrate stocker is a separate device from the solder paste printing device, the upstream side pseudo-substrate stocker requires a separate housing and control unit from the solder paste printing device. This makes the configuration for stirring the solder paste complicated.
In contrast, according to the above-described screen printing machine, since the rolling substrate supply unit is configured as a part of the screen printing machine, the configuration can be simplified compared to when it is configured as a device separate from the screen printing machine.

Furthermore, the upstream pseudo substrate stocker described in Patent Document 1 has a complicated configuration because it is equipped with a magazine that supports the pseudo substrate. In contrast, the above screen printing machine can supply the rolling substrate with two mechanisms: a mechanism for moving a pair of pedestals in the horizontal direction (i.e., the first substrate support part), and a mechanism for raising and lowering the rolling substrate (i.e., the substrate lifting part). These mechanisms can be realized with simple configurations, so the configuration can be simpler than that of the upstream pseudo substrate stocker described in Patent Document 1.
Therefore, the above-mentioned screen printing machine can perform rolling of solder paste with a simple configuration.

(2) The conveyor includes a pair of conveyor belts, a pair of belt support parts supporting each of the conveyor belts, and a belt moving part that moves at least one of the belt support parts toward and away from the other of the belt support parts, and one of the base parts and the moving part that moves the base part may be disposed on one of the belt support parts.

Since the width of the substrate varies depending on the type of substrate, it is preferable that the distance between the pair of moving parts that move the pedestal part in the horizontal direction is also adjusted in accordance with the width of the substrate.
According to the above screen printing machine, when one of the belt support parts is moved to match the width of the substrate, the other of the movable parts also moves, so there is no need to provide a mechanism for adjusting the distance between the pair of movable parts in addition to the mechanism for adjusting the distance between the belt support parts, which simplifies the configuration for adjusting the distance between the pair of movable parts in accordance with the width of the substrate.

(3) The conveyor may have a main conveyor that transports the substrate to the printing position and a sub-conveyor that is arranged upstream or downstream of the main conveyor, and the rolling substrate supply unit may support the rolling substrate above the sub-conveyor.

In the above screen printing machine, the sub-conveyor is positioned so that it does not overlap with the mask, so by supporting the rolling substrate above the sub-conveyor, the rolling substrate can be supported at a position where it does not overlap with the mask.

(4) The solder paste rolling method according to the present disclosure includes a first step of raising the second substrate support part by the lifting unit and lifting the rolling substrate supported by the first substrate support part when a predetermined condition for rolling the solder paste is met, a second step of moving the pair of pedestal parts in a direction away from each other by the moving unit while the rolling substrate is lifted by the second substrate support part, a third step of lowering the second substrate support part by the lifting unit while the pair of pedestal parts are separated from each other, thereby supplying the rolling substrate to the conveyor, and a fourth step of transporting the rolling substrate supplied to the conveyor to the printing position, and rolling the solder paste on the mask by the printing unit while the printing table is in close contact with the lower surface of the mask.

For example, when a certain condition is met, the operator can be notified that solder paste rolling is necessary, and the operator can manually set the rolling substrate. However, in that case, the operator must set the rolling substrate, which hinders labor savings. If the operator cannot set the rolling substrate immediately, there is a possibility that a wait time will occur before solder paste rolling can begin. According to the above solder paste rolling method, solder paste rolling is performed automatically when a certain condition is met, which not only reduces labor costs, but also reduces the wait time before solder paste rolling can begin.

(5) After the rolling of the solder paste is performed using the rolling substrate, the fifth step may be to support the rolling substrate on the conveyor; the sixth step may be to drive the conveyor to transport the rolling substrate below the position supported by the first substrate support part; the seventh step may be to raise the second substrate support part by the lifting part and lift the rolling substrate transported below the position supported by the first substrate support part above the pedestal part; the eighth step may be to move the pair of pedestal parts in a direction approaching each other by the moving part while the rolling substrate is being lifted by the second substrate support part; and the ninth step may be to lower the second substrate support part by the lifting part while the pair of pedestal parts are approaching each other, thereby supporting both ends of the rolling substrate on the pedestal part.

According to the above solder paste rolling method, the rolling substrate can be automatically supported by the rolling substrate supply unit after the rolling of the solder paste is completed. This further promotes labor saving.

(6) After the ninth step is completed, a printing operation for printing a circuit pattern on the substrate may be automatically started.

For example, if an operator wants to instruct the start of a printing operation after solder paste rolling has finished, the operator may be performing another task and be unable to give the instruction immediately, which may result in a wait time before the printing operation can start. With the above solder paste rolling method, the printing operation starts automatically when solder paste rolling has finished, reducing the wait time before the printing operation can start. This improves productivity.

[Details of the embodiment of the present disclosure]
The present disclosure will be described below with reference to the embodiments. The present disclosure is not limited to these examples, but is defined by the claims, and is intended to include all modifications within the meaning and scope of the claims.
The embodiments of the present disclosure can be realized in various forms, such as an apparatus, a method, a computer program for implementing the functions of these apparatuses or methods, and a recording medium on which the computer program is recorded.

<Embodiment 1>
A first embodiment will be described with reference to Figures 1 to 9. In the following description, the front-rear direction, left-right direction, and up-down direction are based on the front-rear direction, left-right direction, and up-down direction shown in Figure 1. In the following description, the right side shown in Figure 1 is referred to as the upstream side, and the left side is referred to as the downstream side. In the following description, the reference numerals in the drawings may be omitted for the same components, with some exceptions.

(1) Configuration of the Screen Printer The appearance of the screen printer 1 according to the first embodiment will be described with reference to Fig. 1. The screen printer 1 is a device that prints a circuit pattern on a substrate using a mask 12C (see Fig. 3). The screen printer 1 includes a box-shaped housing 10. An opening through which the substrate is carried in is formed in the right wall of the housing 10. An opening through which the substrate is carried out is formed in the left wall of the housing 10. The substrate is carried into the housing 10 through the opening in the right wall, and after the circuit pattern is printed inside the housing 10, it is carried out through the opening on the left side.

As shown in FIG. 2, the screen printing machine 1 is equipped with conveyors 11 (entrance side conveyor 11A, main conveyor 11B, and exit side conveyor 11C) that transport the substrate P, a mask member 12, a pair of left and right mask holders 13, a printing table 14, a printing unit 15, and a rolling substrate supply unit 16. These are housed in a housing 10. The entrance side conveyor 11A is an example of a sub-conveyor.

As shown in FIG. 3, the mask member 12 comprises a frame-shaped mask frame 12A and a plate-shaped mask 12C supported inside the mask frame 12A via an elastic member 12B. The mask 12C is made of aluminum or iron, and has an opening (not shown) formed in a shape corresponding to the circuit pattern to be printed. The elastic member 12B is a plate-shaped resin, rubber, or the like.

4, the mask holder 13 is composed of a left mask holder 13 A and a right mask holder 13 B. The mask member 12 is supported by the mask holders 13 at both left and right ends.
The entrance conveyor 11A, the main conveyor 11B, and the exit conveyor 11C each include a pair of front and rear conveyor belts 17 that circulate in the left-right direction. In addition, each conveyor 11 also includes a conveyor drive motor that drives the conveyor belts 17, and a belt movement motor 11D (see FIG. 7) that will be described later. The belt movement motor 11D is an example of a belt movement unit. A detailed description of the conveyor 11 will be given later.

2, the printing table 14 is equipped with a plurality of backup pins 14A, a push-up plate 14B on which the backup pins 14A are erected, and a lifting mechanism 14C that raises and lowers the push-up plate 14B. The lifting mechanism 14C has a ball screw 19 that extends in the vertical direction, a ball nut 20 that screws into the ball screw 19, and a motor (not shown) that rotates the ball nut 20.
When the substrate P is transported by the main conveyor 11B to the printing position A below the mask 12C, the push-up plate 14B is raised by the lifting mechanism 14C. When the push-up plate 14B is raised, the substrate P is lifted by the multiple backup pins 14A and brought into close contact with the lower surface of the mask 12C.

As shown in FIG. 5, the printing unit 15 includes a squeegee head 15A, a movement mechanism 15B for reciprocating the squeegee head 15A in the front-rear direction, a squeegee support portion 15C, and a squeegee 15D.
As shown in FIGS. 2 and 4, the squeegee head 15A is formed in a rectangular shape that is long in the left-right direction.

The movement mechanism 15B will be described with reference to Figure 4. The movement mechanism 15B has a rail (not shown) that supports the right end of the squeegee head 15A so that it can slide in the front-rear direction, a ball nut (not shown) that is fixed to the left end of the squeegee head 15A, a ball screw 21 that is screwed into the ball nut and extends in the front-rear direction, and a motor 23 that rotates the ball screw 21.

As shown in FIG. 5, the squeegee support portion 15C is disposed in front of the squeegee head 15A. The squeegee support portion 15C is disposed on the squeegee head 15A so as to be able to rise and fall, and is equipped with a motor that rotates the squeegee 15D about an axis extending in the left-right direction (perpendicular to the paper surface in FIG. 5), and a motor that raises and lowers the squeegee support portion 15C. The squeegee 15D is a plate-shaped member that extends in the left-right direction. The squeegee 15D is rotatably supported by the squeegee support portion 15C via a pair of left and right arm portions 22. In addition, the printing unit 15 is equipped with a supply portion that supplies solder paste 60 to the upper surface of the mask 12C, etc.

As shown in FIG. 4, the rolling substrate supply unit 16 is disposed above the conveyor 11 at a position that does not overlap with the mask member 12 when viewed from above. More specifically, the rolling substrate supply unit 16 is disposed at a position that overlaps with the entrance conveyor 11A when viewed from above. The rolling substrate supply unit 16 is a mechanism that supplies the rolling substrate RP used for rolling the solder paste 60 to the entrance conveyor 11A. The configuration of the rolling substrate supply unit 16 will be described later.

(1-1) Conveyors The configurations of the entrance side conveyor 11A, main conveyor 11B, and exit side conveyor 11C will be described with reference to Fig. 6. Since the configurations of these conveyors are substantially the same, the entrance side conveyor 11A will be described as an example.
The entrance conveyor 11A includes a pair of conveyor frames 25 (a front conveyor frame 25A and a rear conveyor frame 25B) that support the front conveyor belt 17 so as to be circulatively movable in the left-right direction (the direction perpendicular to the plane of the paper in FIG. 6). The pair of conveyor frames 25 are an example of a belt support portion.

The front conveyor frame 25A is fixed in position in the front-rear direction. In contrast, the rear conveyor frame 25B is movable in the front-rear direction. The entrance conveyor 11A is equipped with a belt movement motor 11D (see Figure 7) that moves the rear conveyor frame 25B in the front-rear direction. By moving the rear conveyor frame 25B in the front-rear direction with the belt movement motor 11D, the spacing between the pair of conveyor belts 17 can be adjusted according to the width of the substrate P.

6, the configuration of the rolling substrate supply unit 16 will be described. The rolling substrate supply unit 16 includes two plate members 26 (front plate member 26A and rear plate member 26B) fixed to the underside of each conveyor frame 25 of the entrance conveyor 11A, a first substrate support unit 27, and a substrate lift unit 28.

The front plate member 26A is fixed to the underside of the front conveyor frame 25A and extends rearward. The rear plate member 26B is fixed to the underside of the rear conveyor frame 25B and extends frontward. The board lifting section 28 is arranged on these plate members 26.

The first substrate support section 27 has a pair of pedestals 30 spaced apart in the front-to-rear direction (an example of the horizontal direction) above the entrance-side conveyor 11A, and an air cylinder 31 (a front air cylinder 31A and a rear air cylinder 31B) provided for each pedestal section 30 to move the pedestal section 30 in the front-to-rear direction. The air cylinder 31 is an example of a moving section.
The pair of pedestals 30 are members that support both ends of the rolling substrate RP from below. The front pedestal 30 is formed in an L-shape when viewed from the right side. The rear pedestal 30 is formed in an inverted L-shape when viewed from the right side.

The front air cylinder 31A is disposed on the upper surface of the front conveyor frame 25A. The front air cylinder 31A has a cylindrical plunger 32 that is disposed in an orientation extending in the front-to-rear direction, and a syringe 33 that moves the plunger 32 in the front-to-rear direction. The syringe 33 is connected to an air supply device (not shown). The rear air cylinder 31B is similar, and has a plunger 32 and a syringe 33.

The front base 30 is fixed to the rear end of the plunger 32. The rear base 30 is fixed to the front end of the plunger 32. When positive pressure is supplied to the two air cylinders 31, the two bases 30 move toward each other, and when negative pressure is supplied, the two bases 30 move away from each other. This changes the front-to-rear spacing between the pair of bases 30.

The substrate lifting section 28 is a mechanism for lifting and lowering the rolling substrate RP supported by the first substrate support section 27. As shown in Fig. 4, the substrate lifting section 28 is equipped with four air cylinders 34. As shown in Fig. 6, of the four air cylinders 34, the two front air cylinders 34 are provided on the upper surface of the front plate member 26A behind the front conveyor belt 17. The two rear air cylinders 34 are provided on the upper surface of the rear plate member 26B ahead of the rear conveyor belt 17.
Each air cylinder 34 has a cylindrical plunger 35 (an example of a second substrate support portion) disposed in an orientation extending in the vertical direction, and a syringe 36 (an example of an elevation portion) that raises and lowers the plunger 35. When positive pressure is supplied to the syringe 36, the plunger 35 rises, and when negative pressure is supplied, the plunger 35 descends.

(2) Electrical Configuration of the Screen Printing Machine The electrical configuration of the screen printing machine 1 will be described with reference to Fig. 7. The screen printing machine 1 includes a control unit 50, a display unit 51, and an input unit 52.
The control unit 50 includes a CPU 50A, a RAM 50B, and a storage unit 50C. The storage unit 50C stores various programs and data executed by the CPU 50A. The control unit 50 is connected to a display unit 51, an input unit 52, the conveyor 11, the printing table 14, the printing unit 15, a rolling substrate supply unit 16, and the like. The display unit 51 is a display device such as a liquid crystal display. The input unit 52 is an input device such as a touch panel, a mouse, or a keyboard.

(3) Solder Paste Rolling Process The solder paste rolling process executed by the control unit 50 will be described with reference to Fig. 8. This process is executed every time before printing a circuit pattern on the substrate P.
In S101, the control unit 50 judges whether or not a predetermined condition for rolling the solder paste is satisfied. The predetermined condition is that printing has been stopped for a certain period of time, that a print inspection machine disposed downstream of the screen printing machine 1 has detected fading of the circuit pattern, etc. The predetermined condition is not limited to these and can be determined as appropriate. The predetermined condition may be set by an operator, or may be fixedly set in the screen printing machine 1 in advance. If the predetermined condition is satisfied, the control unit 50 proceeds to S102, and if not, proceeds to S103.

In S102, the control unit 50 controls each part of the screen printing machine 1 to roll the solder paste. The rolling of the solder paste will be described later.
In S103, the control unit 50 prints a circuit pattern on the substrate P. If solder paste rolling has been performed in S102, the printing operation is automatically started after the rolling of the solder paste has been completed.

(4) Rolling of solder paste The rolling of solder paste performed in S102 will be described with reference to FIG. 5. Although a normal substrate P is shown in FIG. 5, for convenience, the substrate P is assumed to be a substrate RP for rolling. The rolling of solder paste is performed in a state where the substrate RP for rolling is in close contact with the lower surface of the mask 12C. The example shown in FIG. 5 shows a case where the solder paste 60 on the mask 12C is rolled from the rear side to the front side. In this case, the control unit 50 lowers the squeegee support unit 15C behind the solder paste 60, and moves the squeegee 15D to the front side by the moving mechanism 15B. When the squeegee 15D moves to the front side, the solder paste 60 is pushed by the squeegee 15D and moves while rolling to the front side. This causes the solder paste 60 to be rolled.

When rolling solder paste 60, the following operations are performed: supplying a rolling substrate RP to the entrance conveyor 11A, rolling the solder paste 60 using the supplied rolling substrate RP, and returning the rolling substrate RP to the rolling substrate supply section 16 after the rolling of the solder paste 60 is completed. Each operation is described below.

(4-1) Operation of Supplying a Rolling Substrate Fig. 9A shows a state in which a rolling substrate RP is supported by the first substrate support part 27 of the rolling substrate supply part 16. As shown in Fig. 9B, the control part 50 raises the plunger 35 by supplying positive pressure to the four air cylinders 34 of the substrate lifting part 28. When the plunger 35 rises, the rolling substrate RP supported by the pedestal part 30 of the first substrate support part 27 is lifted (an example of a first step).

As shown in FIG. 9C, while the rolling substrate RP is being lifted by the substrate lifting unit 28, the control unit 50 supplies negative pressure to the pair of air cylinders 31 of the first substrate support unit 27 to move the pair of pedestals 30 in a direction away from each other (an example of the second step). This results in the pair of pedestals 30 not being positioned below the rolling substrate RP.

As shown in FIG. 9D, the control unit 50 lowers the rolling substrate RP by supplying negative pressure to the air cylinder 34 of the substrate lifting unit 28. When the rolling substrate RP lowers, the front and rear ends of the rolling substrate RP are supported by a pair of conveyor belts 17 of the entrance conveyor 11A. This causes the rolling substrate RP to be supplied to the entrance conveyor 11A (an example of the third process).

(4-2) Operation of rolling solder paste The control unit 50 transports the rolling substrate RP supplied to the entrance conveyor 11A downstream and passes it to the main conveyor 11B. The control unit 50 transports the rolling substrate RP to the printing position A by the main conveyor 11B and raises the printing table 14 to bring the rolling substrate RP into close contact with the lower surface of the mask 12C. This results in the state shown in Figure 5 described above. The control unit 50 rolls the solder paste 60 by moving the squeegee 15D in the state shown in Figure 5 (an example of the fourth step).

(4-3) Operation of Returning the Rolling Substrate to the Rolling Substrate Supply Unit When the rolling of the solder paste 60 is completed, the control unit 50 lowers the printing table 14. When the printing table 14 lowers, the rolling substrate RP is supported by the main conveyor 11B (an example of the fifth step). In this state, the control unit 50 reverses the rotation of the main conveyor 11B to transport the rolling substrate RP upstream. At this time, the control unit 50 also reverses the rotation of the entrance conveyor 11A. As a result, the rolling substrate RP transported upstream is handed over to the entrance conveyor 11A and transported upstream.

The control unit 50 stops the entrance conveyor 11A when the rolling substrate RP transported upstream reaches a position above the four air cylinders 34 (an example of the sixth step). Figure 9D shows the state in which the rolling substrate RP has reached a position above the four air cylinders 34. The position above the four air cylinders 34 can also be said to be below the position where the rolling substrate RP is supported by the first substrate support part 27.

As shown in Fig. 9C, the control unit 50 raises the rolling substrate RP above the pedestal 30 by supplying positive pressure to the air cylinder 34 (an example of a seventh step). In the state shown in Fig. 9C, the control unit 50 supplies positive pressure to the left and right pedestals 30, thereby moving the pedestals 30 in directions approaching each other (an example of an eighth step). As a result, the pair of pedestals 30 are positioned below the rolling substrate RP as shown in Fig. 9B.
The control unit 50 supplies negative pressure to the air cylinder 34 in the state shown in Fig. 9B to lower the plunger 35. As a result, the rolling substrate RP is supported by the pair of pedestals 30 as shown in Fig. 9A (an example of a ninth step).

(5) Cleaning of the Rolling Substrate As shown in Fig. 9A, an operator of the screen printing machine 1 can remove the rolling substrate RP and clean it when the rolling substrate RP is supported by the rolling substrate supply unit 16. The rolling substrate RP can be removed even when the screen printing machine 1 is performing a printing operation. Therefore, the rolling substrate RP can be cleaned while the printing operation of the screen printing machine 1 is continued.

(6) Effects of the embodiment According to the screen printing machine 1, since the rolling substrate supply unit 16 is configured as a part of the screen printing machine 1, the configuration can be simplified compared to when it is configured as a device separate from the screen printing machine 1. Furthermore, according to the screen printing machine 1, the supply of the rolling substrate RP can be realized by two mechanisms: a mechanism for moving the pair of pedestals 30 in the forward and backward directions (i.e., the first substrate support unit 27), and a mechanism for raising and lowering the rolling substrate RP (i.e., the substrate lifting unit 28). Since these mechanisms can be realized with a simple configuration, the configuration can be simplified compared to the upstream pseudo substrate stocker described in Patent Document 1. Therefore, according to the screen printing machine 1, the rolling of the solder paste 60 can be performed with a simple configuration.

According to the screen printing machine 1, when the rear conveyor frame 25B is moved in the front-rear direction to match the width of the substrate P, the rear air cylinder 31B also moves in the front-rear direction, so there is no need to provide a mechanism for adjusting the spacing between the pair of air cylinders 31 in addition to the mechanism for adjusting the spacing between the conveyor frames 25. This simplifies the configuration for adjusting the spacing between the pair of air cylinders 31 according to the width of the substrate P.

According to the screen printing machine 1, the entrance conveyor 11A is positioned so as not to overlap with the mask member 12, so that the rolling substrate RP can be supported above the entrance conveyor 11A so as not to overlap with the mask member 12.

According to the solder paste rolling method of embodiment 1, the rolling of the solder paste 60 is performed automatically when certain conditions are met, which not only reduces the number of workers required but also reduces the waiting time until the rolling of the solder paste 60 begins.

According to the solder paste rolling method of embodiment 1, the rolling substrate RP can be automatically supported by the rolling substrate supply unit 16 after the rolling of the solder paste 60 is completed. This further promotes labor saving.

According to the solder paste rolling method of the first embodiment, the printing operation starts automatically when the rolling of the solder paste 60 is completed, so the waiting time until the start of the printing operation can be reduced. This improves productivity.

<Other embodiments>
The technology disclosed in this specification is not limited to the embodiments described above and in the drawings, and for example, the following embodiments are also included in the technical scope disclosed in this specification.

(1) In the above embodiment, an example has been described in which a pair of pedestal portions 30 move in the front-rear direction. In contrast, a pair of pedestal portions 30 may be arranged spaced apart in the left-right direction, and the pair of pedestal portions 30 may move in the left-right direction (an example of the horizontal direction).

(2) In the above embodiment, the rolling substrate supply unit 16 is arranged in a position overlapping the entrance conveyor 11A when viewed from above. In contrast, the rolling substrate supply unit 16 may be arranged in a position overlapping the exit conveyor 11C (an example of a sub-conveyor) when viewed from above.

(3) In the above embodiment, the air cylinder 31 is used as an example of the moving part that moves the base 30 in the horizontal direction, but the moving part may be a motor.

(4) In the above embodiment, the syringe 36 is used as an example of the lifting unit that lifts and lowers the second substrate support unit (plunger 35) of the substrate lifting unit 28, but the lifting unit may be a motor.

(5) In the above embodiment, an example was described in which the substrate lifting unit 28 has four second substrate support parts (plungers 35), but the number of second substrate support parts is not limited to this and can be determined as appropriate.

(6) In the above embodiment, the cylindrical plunger 35 is described as an example of the second substrate support part of the substrate lifting unit 28, but the shape of the second substrate support part is not limited to this. For example, the second substrate support part may be a plate-shaped member arranged with the plate surface facing in the front-rear direction.

(7) In the above embodiment, only the rear conveyor frame 25B of the entrance conveyor 11A is movable in the front-rear direction, but the front conveyor frame 25A may also be configured to be movable in the front-rear direction.

(8) In the above embodiment, an example was described in which a print inspection machine located downstream of the screen printing machine 1 detects smearing of the circuit pattern, but the screen printing machine 1 may also be provided with a mechanism for detecting smearing of the circuit pattern.

(9) In the above embodiment, the conveyor 11 is composed of three conveyors: an entrance conveyor 11A, a main conveyor 11B, and an exit conveyor 11C. However, these three conveyors 11 may be composed as a single conveyor.

1: Screen printing machine 11: Conveyor 11A: Inlet side conveyor 11A (an example of a sub-conveyor)
11B: Main conveyor 11C: Exit side conveyor (an example of a sub-conveyor)
11D: Belt moving motor (an example of a belt moving unit)
12C: Mask 14: Printing table 15: Printing unit 15D: Squeegee 16: Rolling substrate supply unit 17: Conveyor belt 25: Conveyor frame (an example of a belt support unit)
27: First substrate support section 28: Substrate lifting section 30: Base section 31: Air cylinder (an example of a moving section)
35: Plunger (an example of a second substrate support part)
36: Syringe (an example of an elevator)
60: Solder paste A: Printing position P: Board RP: Rolling board

Claims (6)

A screen printer that prints a circuit pattern on a substrate using a mask,
a conveyor for transporting the substrate to a printing position;
a printing table that brings the substrate, which has been conveyed to the printing position by the conveyor, into close contact with a lower surface of the mask;
a printing unit having a squeegee, the printing unit moving the squeegee while the substrate is in close contact with the lower surface of the mask to roll the solder paste on the mask, thereby printing a circuit pattern on the substrate;
a rolling substrate supply unit that supports a rolling substrate used for rolling the solder paste when a predetermined condition is satisfied and supplies the rolling substrate to the conveyor;
Equipped with
The rolling substrate supply unit includes:
a first substrate support section that supports the rolling substrate above the conveyor at a position that does not overlap with the mask in a top view, the first substrate support section having a pair of pedestal sections that are horizontally spaced apart from each other and a pair of moving sections that move the pedestal sections in the horizontal direction, and supports both ends of the rolling substrate by the pair of pedestal sections;
a substrate lifting unit that lifts and lowers the rolling substrate supported by the first substrate supporting unit, the substrate lifting unit having a second substrate supporting unit that supports the rolling substrate from below and a lifting unit that lifts and lowers the second substrate supporting unit;
A screen printing machine having a 2. The screen printing machine according to claim 1,
The conveyor includes a pair of conveyor belts, a pair of belt support sections supporting the respective conveyor belts, and a belt moving section that moves at least one of the belt support sections toward and away from the other belt support section.
Equipped with
a first base portion and a second base portion that moves the first base portion, the first base portion being disposed on one of the belt support portions; The screen printing machine according to claim 1 or 2,
the conveyor includes a main conveyor that transports the substrate to the printing position, and a sub-conveyor that is disposed upstream or downstream of the main conveyor;
The rolling substrate supply unit supports the rolling substrate above the sub-conveyor. A solder paste rolling method using the screen printer according to any one of claims 1 to 3, comprising:
a first step of raising the second substrate support part by the lifting part and lifting the rolling substrate supported by the first substrate support part when a predetermined condition for rolling the solder paste is satisfied;
a second step of moving the pair of pedestals in directions away from each other by the moving part while the rolling substrate is lifted by the second substrate supporting part;
a third step of lowering the second substrate support unit by the lift unit while the pair of base units are spaced apart from each other, thereby supplying the substrate for rolling to the conveyor;
a fourth step of conveying the rolling substrate supplied to the conveyor to the printing position, and rolling the solder paste on the mask by the printing unit while the rolling substrate is in close contact with the lower surface of the mask by the printing table;
A method for rolling solder paste comprising: 5. The solder paste rolling method according to claim 4, further comprising the steps of:
a fifth step of supporting the rolling substrate on the conveyor after the solder paste has been rolled using the rolling substrate;
a sixth step of driving the conveyor to transport the rolling substrate to a position below the position where the substrate is supported by the first substrate support portion;
a seventh step of raising the second substrate support part by the lifting part, and lifting the rolling substrate, which has been transferred to a position below the position supported by the first substrate support part, above the pedestal part;
an eighth step of moving the pair of pedestals in directions approaching each other by the moving part while the rolling substrate is lifted by the second substrate supporting part;
a ninth step of lowering the second substrate support part by the lifting part while the pair of pedestals are close to each other, thereby supporting both ends of the rolling substrate on the pedestal parts;
A method for rolling solder paste comprising: 6. The solder paste rolling method according to claim 5, further comprising the steps of:
A solder paste rolling method, wherein after the ninth step is completed, a printing operation for printing a circuit pattern on the board is automatically started.

Images