阅读说明：本技术 丝网印刷装置 (Screen printing apparatus ) 是由 藤本猛志 于 2018-01-10 设计创作，主要内容包括：丝网印刷装置(1)包括:具备可收纳印刷作业部(2A)和丝网掩模(7)的多个收纳部(17a、17b)的掩模保管部(2B)；使丝网掩模(7)在各收纳部(17a、17b)和印刷作业部(2A)之间输送的输送装置(10、14)；被配置在印刷作业部(2A)、在所述输送之际引导丝网掩模(7)的间隔可变的一对第一引导部件(30)；被配置在所述收纳部(17a、17b)、在所述输送之际引导丝网掩模(7)的一对第二引导部件52；判断一对第一引导部件30的间隔是否与一对第二引导部件的间隔(52)一致的引导宽度判断装置(80、60)。(A screen printing apparatus (1) includes a mask storage section (2B) having a plurality of storage sections (17a, 17B) capable of storing a printing operation section (2A) and a screen mask (7); conveying devices (10, 14) for conveying the screen mask (7) between the storage sections (17a, 17b) and the printing operation section (2A); a pair of first guide members (30) which are arranged in the printing operation section (2A) and have a variable interval for guiding the screen mask (7) during the conveyance; a pair of second guide members 52 arranged in the storage sections (17a, 17b) and guiding the screen mask (7) during the conveyance; and guide width determination means (80, 60) for determining whether or not the distance between the pair of first guide members (30) matches the distance between the pair of second guide members (52).)

1. A screen printing apparatus characterized by comprising:

a print job unit that executes a print job;

a mask storage unit which is arranged on a side surface of the printing operation unit and includes a plurality of storage units capable of storing the screen mask;

a conveying device for conveying the screen mask between each of the storage portions of the mask storage portion and the printing operation portion to move the screen mask in a horizontal first direction;

a pair of first guide members, which are disposed at the printing operation section with a variable interval therebetween and are spaced apart from each other in a second direction perpendicular to the first direction, and which guide the screen mask during the conveyance;

a pair of second guide members disposed at intervals in a second direction perpendicular to the first direction in the respective storage portions of the mask storage portion, for guiding the screen mask during the conveyance;

and a guide width determination device that determines whether or not the interval between the pair of first guide members coincides with the interval between the pair of second guide members before the screen mask starts to be conveyed by the conveyance device.

2. A screen printing apparatus according to claim 1,

the guide width determination device includes a sensor including a detection portion attached to one of the first guide members and the second guide members and a detected portion attached to the other of the first guide members and the second guide members, and determines that the distance between the pair of first guide members matches the distance between the pair of second guide members when the detected portion is detected by each of the detection portions.

3. A screen printing apparatus according to claim 2,

the detection unit and the detection target unit are attached to positions facing each other in the first direction in a state where a distance between the pair of first guide members and a distance between the pair of second guide members are matched,

the detection unit detects the detected unit at a position opposite to the detected unit in a first direction.

4. A screen printing apparatus according to any one of claims 1 to 3, characterized by comprising:

and notifying means for notifying, when the guide width determination means determines that the interval between the pair of first guide members does not coincide with the interval between the pair of second guide members.

Technical Field

The present invention relates to a screen printing apparatus for applying paste such as solder paste to a substrate such as a printed circuit board.

Background

Conventionally, there has been known a Screen Printing apparatus in which a Screen mask is laminated on a printed circuit board or the like, paste such as solder paste is moved over the Screen mask by using a squeegee, and the paste is applied (printed) on the board through an opening (mask opening) formed in the Screen mask.

In such a screen printing apparatus, it is necessary to replace the screen mask according to the kind of the substrate, and for example, patent document 1 discloses a screen printing apparatus in which the screen mask can be automatically replaced according to the kind of the substrate.

Such a screen printing apparatus includes a mask storage unit that stores a plurality of types of screen masks in a plurality of stages in the vertical direction, and a conveying device that conveys the screen masks. Although not specifically mentioned, a pair of guide members that support and guide both ends of the screen mask are provided in each of the print job part and the mask storage part, and the screen mask can be considered as a member that moves between the print job part and the mask storage part along the pair of guide members.

However, in the screen printing apparatus having a function of automatically replacing the screen mask, it is considered that a plurality of kinds of screen masks having mutually different sizes can be selectively used. In this case, the interval between the pair of guide members on the printing operation unit side needs to be changed according to the size of the screen mask. Therefore, if the interval is not appropriately changed, a device failure occurs immediately. For example, if the space between the pair of guide members on the printing operation unit side is narrower than the screen mask when the screen mask is conveyed from the mask accommodating unit to the printing operation unit, the screen mask collides with the guide members, and a failure such as a breakage of the screen mask occurs. Therefore, such a failure needs to be prevented, but such a configuration is not disclosed or suggested in patent document 1.

(Prior art document)

(patent document)

Patent document 1 Japanese patent publication No. 3401798

Disclosure of Invention

The invention aims to provide a technology which can prevent the occurrence of faults caused by poor adjustment of the interval of a guide component for guiding a screen mask in a screen printing device with an automatic replacement function of the screen mask.

Further, a screen printing apparatus of the present invention includes: a print job unit that executes a print job; a mask storage portion arranged on a side surface of the printing operation portion and having a plurality of storage portions capable of storing the screen mask; a conveying device for conveying the screen mask between each storage portion of the mask storage portion and the printing operation portion and moving the screen mask in a horizontal first direction; a pair of first guide members, which are disposed in the printing operation section at an interval in a second direction perpendicular to the first direction and guide the screen mask at a variable interval during the conveyance; a pair of second guide members disposed at each of the storage portions of the mask storage portion at an interval in a second direction perpendicular to the first direction, for guiding the screen mask during the conveyance; guide width determination means for determining whether or not the interval between the pair of first guide members matches the interval between the pair of second guide members before the start of the conveyance of the screen mask by the conveyance means.

Drawings

Fig. 1 is a schematic configuration diagram (side view) of a screen printing apparatus according to an embodiment of the present invention.

Fig. 2 is a schematic plan view of the print work section and the mask storage section.

Fig. 3 is a view in the direction of arrow a in fig. 2 showing a mask storage portion (mask stocker).

Fig. 4 is a flowchart for explaining the replacement process control of the screen mask.

Fig. 5 is an explanatory diagram of the screen mask replacement operation (a state where the printing unit is arranged at the conveyance start position in the print working unit).

Fig. 6 is an explanatory diagram of the replacement operation of the screen mask (a state where the second mask is stored in the mask stocker).

Fig. 7 is an explanatory diagram of the replacement operation of the screen mask (a state in which the mask stocker is arranged at the lowered position).

Fig. 8 is an explanatory diagram of the screen mask replacement operation (a state where the printing unit is arranged at the conveyance start position in the mask storage unit).

Fig. 9 is an explanatory diagram of the replacement operation of the screen mask.

Fig. 10 is a schematic plan view of the print job section and the mask storage section (a state where the interval between the guide members of the mask holding unit and the interval between the guide members of the mask stocker do not match).

Detailed Description

Fig. 1 is a schematic configuration diagram (side view) of a screen printing apparatus 1 according to an embodiment of the present invention. In the figure, XYZ rectangular coordinate axes are used to clarify the directional relationship. The X direction is a horizontal direction, the Z direction is an up-down direction, and the Y direction is a direction perpendicular to both the X direction and the Z direction.

The screen printing apparatus 1 (hereinafter, simply referred to as a printing apparatus 1) includes a printing work section 2A for performing printing on a substrate P such as a printed circuit board, and a mask storage section 2B for storing a screen mask for replacement disposed on a side surface thereof. The print working unit 2A and the mask storage unit 2B are disposed adjacent to each other in the X direction.

The printing unit 2A includes a mask holding unit 6, a substrate holding unit 8, and a printing unit 10.

The substrate holding unit 8 includes an upper unit 8A and a lower unit 8B. The upper unit 8A holds the substrate P during the printing operation. The upper unit 8A includes a conveyor belt 20 for conveying the substrate P, a substrate support mechanism 22 for lifting up the substrate P from the conveyor belt 20 and supporting the substrate P, and a substrate holding mechanism 24 for holding the substrate P lifted up from the conveyor belt 20 by the substrate support mechanism 22. The substrate P is carried onto the conveyor 20 from the upstream side in the Y direction (the back side in the direction perpendicular to the paper surface of fig. 1), and is held in a state of being positioned in the upper unit 8A by the respective mechanisms 22 and 24. After the printing process, the positioned state is released, and the sheet is conveyed to the downstream side in the Y direction (front side in the direction perpendicular to the sheet surface of fig. 1) by the conveyor belt 20.

The lower unit 8B moves the substrate P positioned in the upper unit 8A together with the upper unit 8A. Although not shown in detail, the lower unit 8B includes a table and a drive mechanism using a servomotor as a drive source for displacing the table in directions X, Y, Z and R. Also, the upper unit 8A is fixed on the table. With this configuration, the substrate holding unit 8 moves the substrate P in the directions X, Y, Z and R.

The mask holding unit 6 is disposed above the substrate holding unit 8. The mask holding unit 6 holds a screen mask 7 (hereinafter, simply referred to as a mask 7). As shown in fig. 2, the mask 7 is rectangular (rectangular or square) in plan view, and includes a mask main body 70 formed of a thin metal plate having a printing opening formed therein, and a frame body 72 made of metal (e.g., aluminum) and bridging the mask main body 70.

The mask holding unit 6 includes a pair of guide members 30 arranged at an interval in the Y direction and extending parallel to each other in the X direction, a mask clamping device 32 for clamping the mask 7 between the pair of guide members 30, and an interval varying mechanism 34 for varying the interval between the pair of guide members 30. In fig. 1, the mask holding device 32 and the interval varying mechanism 34 are omitted for convenience.

As shown in fig. 2, each guide member 30 is a member having an L-shaped cross section and including a support portion 30a having a support surface for supporting the mask 7 and a guide portion 30b having a guide surface for restricting the screen mask 7 from the outside in the Y direction, and is formed of a metal material such as stainless steel.

A mask holding device 32 is provided at each guide member 30. Although not shown in detail, the mask clamping device 32 is composed of a clamping plate and a cylinder for driving the clamping plate to advance and retreat, and the mask 7 (part of the frame 72) is clamped between the supporting part 30a of the guide member and the clamping plate, thereby fixing the mask 7 to the guide member 30. In this example, two mask holding devices 32 are provided to one guide member 30 at a predetermined interval in the X direction (the longitudinal direction of the guide member 30).

The interval variable mechanism 34 is a screw feed mechanism. Specifically, the interval varying mechanism 34 includes a pair of guide rails 36 extending in the Y direction and movably supporting the guide members 30, a screw shaft 37 extending in the Y direction and fixed to the guide members 30 and threadably inserted into a nut member not shown, and a servomotor 38 driving the screw shaft 37. That is, the variable interval mechanism 34 moves the guide member 30 along the guide rail 36 by rotationally driving the screw shaft 37 by the servo motor 38. Further, a pair of guide rails 36, a threaded shaft 37, a nut member, and a servomotor 38 are provided for each guide member 30.

The printing unit 10 is movably disposed above the mask holding unit 6. The printing unit 10 moves the paste along the upper surface of the mask 7 (mask main body 70). Examples of the paste include a conductive bonding material such as solder paste and conductive paste.

The printing unit 10 is provided to be movable in the X direction by a screw feed mechanism. Specifically, the printing unit 10 includes a beam 11 extending in the Y direction, and both ends of the beam 11 movably support guide rails 40 extending in the X direction. Nut members are built in both ends of the beam 11, and when the screw shaft 42 extending in the X direction is screwed into the nut members, the nut members are coupled to the servomotor 44. The servo motor 44 rotationally drives the screw shaft 42, and the printing unit 10 moves in the X direction along the guide rail 40.

The guide rail 40 and the screw shaft 42 extend from the position of the print working unit 2A to the position of the mask storage unit 2B in the X direction. The beam 11 has a length dimension that allows the mask holding unit 6 and a mask stocker 16 described later to cross in the Y direction. Therefore, the printing unit 10 is movable in the X direction from the print job part 2A to the mask storage part 2B.

The printing unit 10 is also provided with a squeegee 12 and a mask slider 14. The scraper 12 is a metal plate-like member having a pressing surface for pressing the paste. The paste moves by being pressed against the mask 7 by the squeegee 12. The squeegee 12 reciprocates in the X direction integrally with the printing unit 10, and changes its posture so that the pressing surface faces forward in the traveling direction when moving forward and when moving backward. Further, the squeezee 12 is movable in the Z direction between a position (a position shown by a two-dot chain line in fig. 1) slidably contacting the mask main body 7a and a position retreated above the mask 7.

The mask slider 14 is used to move the mask 7 between the print operation unit 2A and the mask storage unit 2B.

The mask slide block 14 includes a pin 14a extending in the Z direction, and a driving portion 14b such as an air cylinder that drives the pin 14a to advance and retract in the Z direction (see fig. 5). The pins 14a are provided so that their tips (lower ends) can be displaced between a lowered position, which is a predetermined protruding position that is lower than the upper surface of the mask 7 supported by the guide member 30 and higher than the upper surface of the mask body 70, and a raised position, which is a retracted position retracted from the lowered position to above the mask 7. In fig. 1, the position shown by the solid line is the projecting position of the plug 14a, and the position shown by the two-dot chain line is the retracted position of the plug 14 a. That is, the mask slider 14 moves the mask 7 in the X direction in accordance with the movement of the printing unit 10 by hooking the pins 14a to the frame 72. In this example, the printing unit 10 including the mask slider 14 corresponds to the "conveying device" of the present invention.

On the other hand, a mask storage 16 is disposed in the mask storage 2B. The mask stocker 16 stores a plurality of masks 7.

As shown in fig. 1 to 3, the mask stocker 16 has upper and lower storage portions 17a and 17b for storing the masks 7, and two types of masks 7 having different mask opening patterns and sizes are stored in the storage portions 17a and 17 b. Specifically, the mask 7 having a small size (appropriately referred to as a first mask 7A) is accommodated in the accommodating portion 17A (appropriately referred to as a first accommodating portion 17A) on the upper layer, and the mask 7 having a larger size than the first mask 7A (appropriately referred to as a second mask 7B) is accommodated in the accommodating portion 17B (appropriately referred to as a second accommodating portion 17B) on the lower layer. Fig. 1 to 3 show a state in which the second mask 7B is disposed in the print job part 2A and only the first mask 7A is stored in the mask stocker 16.

The mask stocker 16 is constituted by a pair of mask support frames 50 made of a metal material such as aluminum disposed at a predetermined interval in the Y direction. Each mask support frame 50 includes an upper stage portion 51a having a flat and horizontal support surface, a lower stage portion 51b having a similar support surface, and a guide member 52 fixed to each stage portion 51a, 51 b. The respective shelf portions 51a, 51b and the guide member 52 extend with the same length in the X direction.

Each guide member 52 is a member having an L-shaped cross section and including a guide portion 53B having a guide surface for regulating the mask 7 from the outside in the Y direction and a fixing portion 53a for fixing the guide member 52 to each frame portion 51a, 51B, and is fixed to each frame portion 51a, 51B via the fixing portion 53a by a bolt B. As shown in fig. 3, the guide surface of the guide portion 53b and the support surface of each of the frame portions 51a and 51b are arranged at right angles to each other, and the fixing portion 53a extends outward (outward in the Y direction) from the guide portion 53 b. According to this configuration, the first mask 7A is accommodated in the first accommodating portion 17A in a state in which both end portions thereof are supported by the respective upper frame portions 51a and are restricted from the outside in the Y direction by the guide portions 53b of the guide member 52. The second mask 7B is accommodated in the second accommodating portion 17B in a state where both end portions thereof are supported by the lower stage portions 51B and are restricted from the outside in the Y direction by the guide portions 53B of the guide members 52.

In each of the rack portions 51a and 51b, a thread row composed of a plurality of screw holes Bh arranged at a predetermined interval in the X direction is provided in two rows at a predetermined interval in the Y direction. These screw rows are used for fixing the guide member 52, and the screw holes Bh of the inner and outer screw rows are used, whereby the interval between the guide members 52 can be made two stages wider and narrower. In this example, the guide members 52 are fixed to the respective upper frame portions 51a by using the respective screw holes Bh of the inner screw row, so that the intervals of the guide members 52 are narrow intervals corresponding to the first mask 7A; the lower stage portion 51B is fixed with the guide members 52 using the screw holes Bh of the outer thread row, and the interval between the guide members 52 is set to a wide interval corresponding to the second mask 7B.

Each mask support frame 50 is supported by an apparatus frame, not shown, so as to be able to move up and down, and is connected to the air cylinder 18. Also, by synchronously driving the air cylinders 18, the two mask support frames 50 can be integrally lifted and lowered. That is, the mask stocker 16 is driven by the air cylinder 18 to raise and lower the first storage portion 17a to and from the lowered position corresponding to the mask holding unit 6, and to raise and lower the second storage portion 17b to and from the raised position corresponding to the mask holding unit 6. The lowered position is a position where the position of the support surface of the support portion 30a of the guide member 30 and the position of the support surface of the upper stage portion 51a are equal to each other in the Z direction, and the raised position is a position where the position of the support surface of the support portion 30a of the guide member 30 and the position of the support surface of the lower stage portion 51b are equal to each other in the Z direction.

Further, a photosensor 60 is provided on each guide member 30 of the mask holding unit 6 and the guide member 52 of each housing portion 17a, 17b of the mask stocker 16. The photoelectric sensor 60 is used to detect whether or not the interval (i.e., the guide width) between the guide portions 30b of the pair of guide members 30 matches the interval between the guide portions 53b of the pair of guide members 52.

As shown in fig. 2, the photoelectric sensor 60 includes a sensor body 61 including a projector and a light receiver, and a reflector 62 as an object to be detected. The sensor body 61 is fixed to an end (right end in fig. 2) of each guide member 30 on the mask storage 2B side, and the reflection plate 62 is fixed to an end (left end in fig. 2) of each guide member 52 on the print working unit 2a side. Both the sensor body 61 and the reflection plate 62 are fixed to the side surfaces of the guide portions 30b and 53b on the opposite guide surface sides.

That is, when the distance Wa between the guide portions 30b of the pair of guide members 30 and the distance Wb between the guide portions 53b of the pair of guide members 52 are equal (equal), the sensor body 61 and the reflection plate 62 face each other in the X direction, and thus the projection light from the sensor body 61 is reflected by the reflection plate 62 and received by the sensor body 61. That is, the reflection plate 62 is detected. Thereby, the sensor main body 61 outputs a predetermined high (Hi) level signal. On the other hand, when the interval Wa between the guide portions 30b of the pair of guide members 30 and the interval Wb between the guide portions 53b of the pair of guide members 52 do not coincide, the sensor body 61 and the reflection plate 62 are displaced in the Y direction. For this reason, the light from the sensor body 61 is not reflected by the reflection plate 62, that is, the reflection plate 62 is not detected, and the sensor body 61 outputs the Lo level signal lower than the high level signal level. The control device 80 (arithmetic processing unit 81), which will be described later, determines whether or not the interval between the guide portions 30b of the pair of guide members 30 and the interval between the guide portions 53b of the pair of guide members 52 match based on the output signal from the photoelectric sensor 60. In this example, the photosensor 60 and the control device 80 (the arithmetic processing unit 81) correspond to the "guide width determination device" of the present invention, and the photosensor 60, the sensor body 61, and the reflection plate 62 correspond to the "sensor", "detection unit", and "detection unit" of the present invention, respectively.

In addition, reference numeral 4 in fig. 1 is a camera unit. The camera unit 4 includes a camera 4a for imaging the substrate P held by the substrate holding unit 8, an illumination device, and the like. The camera unit 4 is provided so as to be movable in the X direction between a position interposed between the mask holding unit 6 and the substrate holding unit 8 and a position located below the mask stocker 16 retracted from the position, in a state where the substrate P held by the substrate holding unit 8 is spaced apart from the mask 7 (the state shown in fig. 1).

The outline of the printing operation of the printing apparatus 1 is as follows. That is, the substrate P is held by the upper unit 8A of the substrate holding unit 8, and is remounted below the mask 7 in accordance with the operation of the lower unit 8B. Then, in this state, the paste on the mask main body 70 is moved by the squeegee 12 by the reciprocating movement of the printing unit 10 in the X direction. As a result, the paste is applied (printed) on the substrate P. The printed substrate P is separated from the mask 7 by the operation of the lower unit 8B, and is transported downstream from the print operation unit 2 by the operation of the transport belt 20 of the upper unit 8A. If necessary, the mask 7 of the print operation unit 2 may be replaced with the mask 7 in the mask stocker 16 in the space of the print operation.

As shown in fig. 1, the printing apparatus 1 includes a control device 80 that integrally controls the entire apparatus. The control device 80 includes an arithmetic processing unit 81, a drive control unit 82, a storage unit 83, an input/output control unit 84, and the like.

The arithmetic processing unit 81 is constituted by a CPU or the like, and controls the operation of each unit of the printing apparatus 1 such as the printing unit 10 and the like through the drive control unit 82 in accordance with a printing program stored in advance in the storage unit 83 to execute the above-described printing process. The arithmetic processing unit 81 executes a mask replacement process, which will be described later, in accordance with a mask replacement program stored in the storage unit 83, based on a command input by an operator through an operation of an input device, not shown, or production plan information input in advance.

An input/output control unit 84 controls input/output of signals between the control device 80 and various sensors and actuators, and the sensor body 61 of the photoelectric sensor 60 is connected to the input/output control unit 84. Further, a warning lamp/speaker 85 is also connected to the input/output control section 84. When the printing apparatus 1 is out of order, the warning lamp/speaker 85 notifies the operator of the failure by light and sound.

Next, control of the mask replacement process performed by the arithmetic processing unit 81 will be described based on the flow of fig. 4 with reference to fig. 5 to 10.

In the following description, the guide member 30 of the mask holding unit 6 is referred to as a "first guide member 30", and the guide member 52 of the mask stocker 16 is referred to as a "second guide member 52". The printing apparatus 1 is assumed to be in the state shown in fig. 1, that is, in the state where the second mask 7B is set in the print job unit 2 and the first mask 7A is stored in the mask storage 16, and the mask storage 16 is arranged at the raised position.

The control is started by, for example, a command input to perform the mask replacement process. When this control is started, the arithmetic processing unit 81 first determines whether or not the interval between the pair of first guide members 30 coincides with the interval between the pair of second guide members 52 on the mask stocker 16 side, more precisely, whether or not the interval Wa between the guide portions 30b of the pair of first guide members 30 coincides with the interval Wb between the guide portions 53b of the pair of second guide members 52, based on the output signal from the photosensor 60 (sensor body 61) (step S1). In the following description, these intervals are simply referred to as "intervals between the first guide members 30" and "intervals between the second guide members 52".

Specifically, the arithmetic processing unit 81 determines that the interval Wa of the first guide member 30 matches the interval Wb of the second guide member 52 when the output signal from each sensor body 61 is a high-level signal, and determines that the interval Wa of the first guide member 30 does not match the interval Wb of the second guide member 52 when the output signal is a Lo-level signal.

If yes is determined in step S1, the arithmetic processing unit 81 controls the printing unit 10 and the like to execute the mask carrying-out operation (step S3).

Specifically, the printing unit 10 is moved so that the pins 14a of the mask slide block 14 are positioned on the opposite side of the mask storage 2B with respect to the second mask 7B, and the mask slide block 14 is operated to place the pins 14a at the projecting positions (see fig. 5). Then, after the clamped state of the second mask 7B by the mask clamping device 32 is released, the printing unit 10 is moved toward the mask storage 2B. That is, the second mask 7B is moved in the X direction together with the printing unit 10 by hooking the pins 14a to the second mask 7B. Thereby, the second mask 7B is conveyed from the mask holding unit 6 to the second storage portion 17B of the mask stocker 16 (see fig. 6). At this time, the second mask 7B is guided along the guide portions 30B of the first guide members 30 and the guide portions 53B of the second guide members 52 and smoothly stored in the second storage portion 17B. Further, since the upper and lower masks 7A and 7B need to be conveyed by the common pins 14a of the mask slider 14, the storage position of the first mask 7A stored in the upper layer is shifted to be located outside the storage position of the second mask 7B in the X direction (on the opposite side of the printing work section 2A), and the entry and exit of the second mask 7B stored in the lower layer are not disturbed.

Next, the arithmetic processing unit 81 determines whether or not the second mask 7B is completely stored (step S5), and if yes, moves the mask stocker 16 from the raised position to the lowered position (see fig. 7), and changes the interval of the first guide member 30 to the interval corresponding to the first mask 7A (step S7). At this time, the latch 14a of the mask slider 14 is moved from the protruding position to the retracted position. Whether or not the second mask 7B is completely stored is determined based on output information from a sensor, not shown, disposed in the second storage portion 17B or output information from a position detection device such as an encoder incorporated in the servo motor 44.

Next, the arithmetic processing unit 81 determines whether or not the interval Wa of the first guide 30 matches the interval Wb of the second guide 52 on the mask stocker 16 side, based on the output signal from the sensor main body 61 (step S9).

If it is determined as "yes", the arithmetic processing unit 81 controls the printing unit 10 and the like and executes the mask loading operation (step S11). Specifically, the printing unit 10 is moved so that the pins 14a of the mask slide block 14 are positioned inside the frame 72 of the first mask 7A, and the mask slide block 14 is operated to place the pins 14a at the projecting positions (see fig. 8). Then, the printing unit 10 is moved toward the print job part 2. That is, the pins 14a are hooked to the frame 72 from the inside of the first mask 7A, and the first mask 7A is moved in the X direction together with the printing unit 10. Thereby, the first mask 7A is conveyed from the first storage portion 17A of the mask stocker 16 to the mask holding unit 6 (see fig. 9). At this time, the first mask 7A is guided along the guide portions 53b of the second guide members 52 of the first storage portion 17A and the guide portions 30b of the first guide member 30 and smoothly conveyed to the mask holding unit 6.

Next, the arithmetic processing unit 81 determines whether or not the conveyance of the first mask 7A to the mask holding unit 6 is completed (step S13), and if yes, moves the pins 14a of the mask slide blocks 14 from the projecting position to the retracted position, operates the mask chucking device 32 to fix the first mask 7A to the first guide members 30, and then ends the present flow. Whether or not the first mask 7A is completely conveyed is determined based on output information from a sensor, not shown, disposed in the mask holding unit 6 or output information from a position detection device such as an encoder incorporated in the servo motor 44.

On the other hand, when the determination in step S1 is no, that is, when the determination is that the interval Wa of the guide portion 30b of the first guide member 30 does not coincide with the interval Wb of the guide portion 53b of the second guide member 52, the arithmetic processing unit 81 determines whether or not the timer is on (step S15), and when the determination is no, the timer is turned on (step S17), and then the air cylinder is operated to move the mask stocker 16 (step S19). Then, it is determined whether or not the predetermined time h1 has elapsed (step S21), and if no, the process proceeds to step S1. That is, when the interval Wa of the guide portion 30b of the first guide member 30 does not coincide with the interval Wb of the guide portion 53b of the second guide member 52, the correspondence relationship between the first guide member 30 and the storage portions 17a and 17b of the mask storage 16 does not coincide, and the arithmetic processing unit 81 moves the mask storage 16 to eliminate this.

When it is determined that the interval Wa of the first guide 30 matches the interval Wb of the second guide 52 until the predetermined time h1 elapses (yes at step S1), the arithmetic processing unit 81 proceeds to step S3. On the other hand, if it is not determined that the interval Wa of the first guide member 30 and the interval Wb of the second guide member 52 match during the elapse of the predetermined time h1, the arithmetic processing unit 81 operates the warning lamp/speaker 85 at the time of the elapse of the predetermined time h1 (step S31), and then ends the present flow.

If it is determined in step S9 that the distance Wa of the guide portions 30b of the first guide members 30 does not coincide with the distance Wb of the guide portions 53b of the second guide members 52 of the first housing member 17a, the arithmetic processing unit 81 first determines whether or not the timer is on (step S23), and if it is determined that the distance Wa does not coincide with the distance Wb of the guide portions 53b of the second guide members 52 of the first housing member 17a, the arithmetic processing unit turns on the timer (step S25), and then operates the servo motor 38 to move the first guide members 30 (step S27). Then, it is determined whether or not the predetermined time h2 has elapsed (step S29), and if no, the process proceeds to step S9. For example, if the amount of movement of each first guide member 30 in step S7 is not complete, the distance Wa of the first guide members 30 may not match the distance Wb of the second guide members 52, and the arithmetic processing unit 81 moves each first guide member 30 to eliminate the situation.

When it is determined that the interval Wa of the first guide 30 matches the interval Wb of the second guide 52 until the predetermined time h2 elapses (yes at step S9), the arithmetic processing unit 81 proceeds to step S11. On the other hand, if it is not determined that the interval Wa of the first guide member 30 and the interval Wb of the second guide member 52 match each other until the predetermined time h2 has elapsed, the arithmetic processing unit 81 shifts the process to step S31 at the time when the predetermined time h2 has elapsed, and then operates the warning lamp/speaker 85, and then the flow ends.

As described above, according to the printing apparatus 1, when the mask 7 is replaced, the arithmetic processing unit 81 determines whether or not the interval Wa of the first guide member 30 of the print working unit 2A (mask holding unit 6) matches the interval Wb of the second guide member 52 of the mask storage unit 2B (mask storage 16) based on the output signal from the photoelectric sensor 60 (sensor body 61). When the interval Wa of the first guide member 30 does not coincide with the interval Wb of the second guide member 52 and is not eliminated until the predetermined times h1 and h2 have elapsed, the warning lamp/speaker 85 is operated to stop the mask 7 conveyance operation. Therefore, it is possible to surely prevent occurrence of a failure due to conveyance of the mask 7 in a state where the interval Wa of the first guide member 30 does not coincide with the interval Wb of the second guide member 52.

For example, in the process of conveying the second mask 7B from the mask holding unit 6 to the mask stocker 16, it is possible to prevent damage caused by collision of the second mask 7B with the second guide member 52 of the first storage portion 17 a. Further, as shown in fig. 10, when the interval Wa of the first guide member 30 is the interval Wb corresponding to the second mask 7B, the first mask 7A is prevented from falling onto the substrate holding unit 8 from between the two first guide members 30 due to the start of the conveyance of the first mask 7A from the mask stocker 16, and the substrate holding unit 8 or the first mask 7A is prevented from being damaged.

Further, according to the printing apparatus 1, the photoelectric sensors 60 (the sensor body 61 and the reflection plate 62) are attached to the first guide members 30 of the mask holding unit 6 and the second guide members 52 of the mask storage 16, and the arithmetic processing unit 81 determines whether or not the interval Wa of the first guide members 30 matches the interval Wb of the second guide members 52 based on the output signal from the photoelectric sensors 60. For this reason, the above-described functional effects can be obtained with a simple structure.

In particular, since the sensor body 61 is mounted on the end of the first guide member 30 and the reflection plate 62 is mounted on the end of the second guide member 52, the sensor body 61 detects the reflection plate 62 (outputs a high-level signal) when the interval of the first guide member 30 coincides with the interval of the second guide member 52, and thus, is very simple in structure. For this reason, there is also an advantage of easy maintenance, that is, daily maintenance for replacing the photoelectric sensor 60 or the like due to a failure.

The printing apparatus 1 described above is an example of a preferred embodiment of the screen printing apparatus of the present invention, and the specific configuration of the printing apparatus 1 may be modified as appropriate within a range not departing from the gist of the present invention.

For example, in the printing apparatus 1, a photosensor is used as the "sensor" of the present invention, but the type of the "sensor" is not limited to this. Various other sensors (including cameras) may also be employed. Further, the detection may be performed directly by using a part of the guide member 52 as the detection target portion, without being limited to the sensor having the dedicated detection target portion (the reflection plate 62) as in the printing apparatus 1. Therefore, a proximity switch such as an inductance type, a capacitance type, or a magnetic type, or a sensor such as a hall element may be used. Further, the sensor is not limited to a non-contact sensor, and a contact sensor such as a micro switch may be used.

In the printing apparatus 1, the printing unit 10 is provided with the mask slider 14 to convey the mask 7 by moving the printing unit 10 in the X direction. However, it is also possible to have a dedicated conveying device for conveying the mask 7 independently of the printing unit 10.

Further, although the mask stocker 16 of the printing apparatus 1 changes the interval between the guide members 52 by attaching and detaching the bolts B, the interval between the second guide members 52 may be changed by a screw feeding mechanism or the like, for example, in the same manner as the first guide member 30 of the mask holding unit 6. With this configuration, the degree of freedom of the interval between the guide members 52 can be increased, and the mask 7 having a wider size can be stored. In this case, the guide member 52 may be moved in addition to the movement of the mask stocker 16 in the process of step S19 in fig. 4.

The present invention described above according to the embodiments is summarized as follows.

The screen printing apparatus of the present invention includes: a print job unit that executes a print job; a mask storage portion arranged on a side surface of the printing operation portion and having a plurality of storage portions capable of storing the screen mask; a conveying device for conveying the screen mask between each storage portion of the mask storage portion and the printing operation portion and moving the screen mask in a horizontal first direction; a pair of first guide members, which are disposed in the printing operation section at an interval in a second direction perpendicular to the first direction and guide the screen mask at a variable interval during the conveyance; a pair of second guide members disposed at each of the storage portions of the mask storage portion at an interval in a second direction perpendicular to the first direction, for guiding the screen mask during the conveyance; guide width determination means for determining whether or not the interval between the pair of first guide members matches the interval between the pair of second guide members before the start of the conveyance of the screen mask by the conveyance means.

In this screen printing apparatus, when the screen mask is conveyed by the conveying device in association with replacement of the screen mask, the guide width determining device determines whether or not the interval of the first guide member on the print work portion side coincides with the interval of the second guide member on the mask storage portion (storage portion) side. For this reason, by controlling the conveying device or the like based on the determination result, it is possible to prevent the screen mask from being conveyed without the interval of the first guide member and the interval of the second guide member being coincident.

In the above configuration, the guide width determination device may include a sensor including a detection portion attached to one of the first guide member and the second guide member and a detection portion attached to the other of the first guide member and the second guide member, and the guide width determination device may determine that the distance between the pair of first guide members matches the distance between the pair of second guide members when the detection portion detects the detection portion.

With this configuration, it is possible to determine whether or not the interval between the first guide members matches the interval between the second guide members with a simple configuration such as a sensor including a detection unit and a detection unit.

In this case, it is preferable that the detection unit and the detected unit are attached to positions facing each other in the first direction in a state where a distance between the pair of first guide members and a distance between the pair of second guide members coincide, and the detection unit detects the detected unit at a position facing the detected unit in the first direction.

With this configuration, the detection unit and the mounting position of the detected unit can be configured with a simpler configuration.

In the screen printing apparatus, it is preferable that the screen printing apparatus further includes a notification device configured to notify that the interval between the pair of first guide members does not coincide with the interval between the pair of second guide members when the guide width determination device determines that the interval does not coincide with the interval between the pair of second guide members.

With this configuration, the operator can recognize early that the interval between the first guide members does not match the interval between the second guide members.

[ description of symbols ]

1 Screen printing apparatus

2A printing operation part

2B mask storage part

7 Screen mask

7A first mask

7B second mask

10 printing unit (conveying device)

14 mask sliding block (conveying device)

17a first receiving part

17b second accommodation part

30 first guide member

52 second guide member

60 photoelectric sensor

61 sensor body (detection part)

62 reflecting board (detected part)

80 control device (guide width judging device)

81 arithmetic processing unit (guide width determination device)

85 warning lights/speakers (annunciator).